Knowledge

Set-builder notation

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There is no order among the elements of a set (this explains and validates the equality of the last example), but with the ellipses notation, we use an ordered sequence before (or after) the ellipsis as a convenient notational vehicle for explaining which elements are in a set. The first few elements
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is clear from context, it may be not explicitly specified. It is common in the literature for an author to state the domain ahead of time, and then not specify it in the set-builder notation. For example, an author may say something such as, "Unless otherwise stated, variables are to be taken to be
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In each preceding example, each set is described by enumerating its elements. Not all sets can be described in this way, or if they can, their enumeration may be too long or too complicated to be useful. Therefore, many sets are defined by a property that characterizes their elements. This
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of the sequence are shown, then the ellipses indicate that the simplest interpretation should be applied for continuing the sequence. Should no terminating value appear to the right of the ellipses, then the sequence is considered to be unbounded.
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The following examples illustrate particular sets defined by set-builder notation via predicates. In each case, the domain is specified on the left side of the vertical bar, while the rule is specified on the right side.
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However, the prose approach may lack accuracy or be ambiguous. Thus, set-builder notation is often used with a predicate characterizing the elements of the set being defined, as described in the following section.
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Two sets are equal if and only if they have the same elements. Sets defined by set builder notation are equal if and only if their set builder rules, including the domain specifiers, are equivalent. That is
4460: 4302:, and set objects, respectively. Python uses an English-based syntax. Haskell replaces the set-builder's braces with square brackets and uses symbols, including the standard set-builder vertical bar. 3087: 1599: 89: 3579: 2598: 2436: 4154: 3248: 1944: 1755: 2353: 1856: 3301: 3185: 1476: 2997: 2213: 1235: 4210: 1523: 2834: 839: 358: 1687: 3689:
Therefore, in order to prove the equality of two sets defined by set builder notation, it suffices to prove the equivalence of their predicates, including the domain qualifiers.
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separator, and a predicate. Thus there is a variable on the left of the separator, and a rule on the right of it. These three parts are contained in curly brackets:
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When inverse functions can be explicitly stated, the expression on the left can be eliminated through simple substitution. Consider the example set
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using Sequence Comprehensions, where the "for" keyword returns a list of the yielded variables using the "yield" keyword.
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natural numbers," though in less formal contexts where the domain can be assumed, a written mention is often unnecessary.
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can be described directly by enumerating all of its elements between curly brackets, as in the following two examples:
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although seemingly well formed as a set builder expression, cannot define a set without producing a contradiction.
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In Python, the set-builder's braces are replaced with square brackets, parentheses, or curly braces, giving list,
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The set builder notation and list comprehension notation are both instances of a more general notation known as
2152: 5952: 5093: 4682: 4560: 4247: 4235: 961: 1190: 5566: 5445: 4979: 4466: 4231: 4168: 1481: 2786: 1337:{\displaystyle \{x\mid x\in E{\text{ and }}\Phi (x)\}\quad {\text{or}}\quad \{x\mid x\in E\land \Phi (x)\}.} 792: 5809: 4998: 4579: 4306: 4299: 313: 1643: 5802: 5440: 5403: 5259: 4243: 225: 2745: 1112: 986: 2470: 365: 5457: 4333: 2600:
is a notational variant for the same set of even natural numbers. It is not necessary to specify that
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for which the predicate is true. This can easily lead to contradictions and paradoxes. For example,
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creates a set of pairs, where each pair puts an integer into correspondence with an odd integer.
2708:{\displaystyle \{a\in \mathbb {R} \mid (\exists p\in \mathbb {Z} )(\exists q\in \mathbb {Z} )\}} 772: 5863: 5744: 5556: 5369: 5109: 4271: 4022: 3887:{\displaystyle (x\in \mathbb {R} \land x^{2}=1)\Leftrightarrow (x\in \mathbb {Q} \land |x|=1).} 3341: 2314: 5130: 3977: 1861: 1394: 5779: 5749: 5693: 5613: 5593: 5571: 4227: 3904: 127: 5208: 3306: 2448: 1604: 1354: 5853: 5843: 5677: 5561: 5501: 5381: 4021:, set builder notation is not part of the formal syntax of the theory. Instead, there is a 3941: 1637: 844: 904:
characterization may be done informally using general prose, as in the following example.
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for which the predicate holds (is true) belong to the set being defined. All values of
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When it is desired to denote a set that contains elements from a regular sequence, an
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obtained from this axiom is exactly the set described in set builder notation as
3783:{\displaystyle \{x\in \mathbb {R} \mid x^{2}=1\}=\{x\in \mathbb {Q} \mid |x|=1\}} 3482:{\displaystyle \{2t+1\mid t\in \mathbb {Z} \}=\{u\mid (u-1)/2\in \mathbb {Z} \}.} 2716: 1758: 2942:{\displaystyle \{f(x)\mid \Phi (x)\}=\{y\mid \exists x(y=f(x)\wedge \Phi (x))\}} 5921: 5718: 5699: 5603: 5588: 5545: 5481: 5423: 2442: 2291:{\displaystyle \{(x,y)\in \mathbb {R} \times \mathbb {R} \mid 0<y<f(x)\}} 1348: 407: 5941: 5926: 5728: 5642: 5637: 2053:{\displaystyle G_{m}=\{x\in \mathbb {Z} \mid x\geq m\}=\{m,m+1,m+2,\ldots \}} 972:
otherwise. In this form, set-builder notation has three parts: a variable, a
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Consider these set-builder notation examples in some programming languages:
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is the set of all natural numbers, is the set of all even natural numbers.
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is the set containing the four numbers 3, 7, 15, and 31, and nothing else.
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Set-builder notation can be used to describe a set that is defined by a
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In general, it is not a good idea to consider sets without defining a
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for which the predicate does not hold do not belong to the set. Thus
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is a natural number, as this is implied by the formula on the right.
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This is sometimes called the "roster method" for specifying a set.
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An extension of set-builder notation replaces the single variable
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is a formula in the language of set theory, then there is a set
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The vertical bar (or colon) is a separator that can be read as "
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Richard Aufmann, Vernon C. Barker, and Joanne Lockwood, 2007,
5581: 5341: 5277: 5135:(6th ed.). New York, NY: McGraw-Hill. pp. 111–112. 111: 4455:{\displaystyle \{(k,x)\ |\ k\in K\wedge x\in X\wedge P(x)\}} 1947: 1081:", "for which", or "with the property that". The formula 138:, or stating the properties that its members must satisfy. 3793:
because the two rule predicates are logically equivalent:
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More complex expressions on the left side of the notation
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notation may be employed, as shown in the next examples:
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Irvine, Andrew David; Deutsch, Harry (9 October 2016) .
3082:{\displaystyle \{p/q\mid p,q\in \mathbb {Z} ,q\not =0\}} 1594:{\displaystyle \{x\in E\mid \Phi _{1}(x),\Phi _{2}(x)\}} 84:{\displaystyle \{n\mid \exists k\in \mathbb {Z} ,n=2k\}} 3574:{\displaystyle \{x\in A\mid P(x)\}=\{x\in B\mid Q(x)\}} 4383: 4336: 4171: 4064: 3980: 3944: 3907: 3802: 3701: 3593: 3507: 3397: 3344: 3309: 3260: 3195: 3144: 3117: 3095: 3029: 3005: 2962: 2845: 2789: 2748: 2614: 2593:{\displaystyle \{n\mid (\exists k\in \mathbb {N} )\}} 2539: 2479: 2451: 2431:{\displaystyle \{n\in \mathbb {N} \mid (\exists k)\}} 2363: 2331: 2223: 2155: 2066: 1965: 1899: 1864: 1808: 1774: 1717: 1646: 1607: 1531: 1484: 1426: 1397: 1357: 1249: 1193: 1115: 1036: 989: 933: 913: 874: 847: 795: 775: 722: 696: 670: 632: 600: 580: 542: 418: 368: 316: 228: 182: 39: 5092:, which permits map/filter-like operations over any 3897:
This equivalence holds because, for any real number
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symbol denotes the logical "and" operator, known as
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is the set of integers between 1 and 100 inclusive.
4454: 4368: 4204: 4149:{\displaystyle (\forall E)(\exists Y)(\forall x).} 4148: 4001: 3966: 3926: 3886: 3782: 3677: 3573: 3481: 3376: 3330: 3295: 3243:{\displaystyle \{(t,2t+1)\mid t\in \mathbb {Z} \}} 3242: 3179: 3128: 3103: 3081: 3013: 2991: 2941: 2828: 2775: 2707: 2592: 2506: 2457: 2430: 2347: 2290: 2207: 2141: 2052: 1938: 1885: 1850: 1792: 1749: 1681: 1613: 1593: 1517: 1470: 1412: 1363: 1336: 1229: 1142: 1066: 1016: 939: 919: 892: 860: 833: 781: 758: 708: 682: 656: 618: 586: 566: 520: 398: 352: 276: 212: 83: 4270:It has been suggested that parts of this page be 2355:denotes the set of ordered pairs of real numbers. 1939:{\displaystyle \{x\in \mathbb {R} \mid x^{2}=1\}} 5939: 3974:. In particular, both sets are equal to the set 1750:{\displaystyle \{x\in \mathbb {R} \mid x>0\}} 2348:{\displaystyle \mathbb {R} \times \mathbb {R} } 1851:{\displaystyle \{x\in \mathbb {R} \mid |x|=1\}} 964:, that is, a logical formula that evaluates to 3296:{\displaystyle \{2t+1\mid t\in \mathbb {Z} \}} 3180:{\displaystyle \{2t+1\mid t\in \mathbb {Z} \}} 2298:is the set of pairs of real numbers such that 1471:{\displaystyle \Phi _{1}(x)\land \Phi _{2}(x)} 955: 158: 5293: 5232: 1184:can appear on the left of the vertical bar: 141:Defining sets by properties is also known as 4449: 4384: 4363: 4337: 4226:A similar notation available in a number of 4199: 4172: 3996: 3981: 3777: 3741: 3735: 3702: 3568: 3541: 3535: 3508: 3473: 3433: 3427: 3398: 3290: 3261: 3237: 3196: 3174: 3145: 3076: 3030: 2992:{\displaystyle \{2n\mid n\in \mathbb {N} \}} 2986: 2963: 2936: 2882: 2876: 2846: 2820: 2790: 2770: 2749: 2702: 2615: 2587: 2540: 2425: 2364: 2285: 2224: 2202: 2172: 2136: 2112: 2106: 2080: 2047: 2011: 2005: 1979: 1933: 1900: 1880: 1865: 1845: 1809: 1744: 1718: 1673: 1647: 1588: 1532: 1512: 1485: 1328: 1295: 1285: 1250: 1221: 1194: 1137: 1116: 1058: 1037: 1011: 990: 934: 914: 828: 796: 753: 735: 651: 633: 561: 543: 515: 473: 467: 419: 393: 369: 347: 317: 271: 253: 247: 229: 207: 183: 78: 40: 4215: 947:is the set of all addresses on Pine Street. 5300: 5286: 4045:whose members are exactly the elements of 2208:{\displaystyle G_{-2}=\{-2,-1,0,\ldots \}} 5132:Discrete Mathematics and its Applications 3852: 3813: 3751: 3712: 3469: 3423: 3286: 3233: 3170: 3119: 3097: 3060: 3007: 2982: 2665: 2645: 2625: 2562: 2465:sign stands for "and", which is known as 2403: 2374: 2341: 2333: 2254: 2246: 2090: 1989: 1910: 1819: 1728: 59: 1388: 1230:{\displaystyle \{x\in E\mid \Phi (x)\},} 1173: 165:Set (mathematics) § Roster notation 5170:A Transition to Mathematics with Proofs 4205:{\displaystyle \{x\in E\mid \Phi (x)\}} 1518:{\displaystyle \{x\in E\mid \Phi (x)\}} 574:denotes the set of all natural numbers 14: 5940: 5172:, Jones & Bartlett, pp. 44ff. 5157:Intermediate Algebra with Applications 4012: 3493:Equivalent predicates yield equal sets 2829:{\displaystyle \{f(x)\mid \Phi (x)\},} 1948:equivalent predicates yield equal sets 1601:, using a comma instead of the symbol 1387:for which the predicate is true (see " 834:{\displaystyle \{a_{1},\dots ,a_{n}\}} 5281: 5181: 5128: 4017:In many formal set theories, such as 3388:in the set builder notation to find 1240:or by adjoining it to the predicate: 353:{\displaystyle \{1,2,3,\ldots ,100\}} 4256: 1682:{\displaystyle \{x~|~x\not \in x\},} 5239:Stanford Encyclopedia of Philosophy 277:{\displaystyle \{a,c,b\}=\{a,b,c\}} 24: 4187: 4128: 4092: 4080: 4068: 3597: 2921: 2891: 2864: 2808: 2776:{\displaystyle \{x\mid \Phi (x)\}} 2758: 2655: 2635: 2552: 2483: 2384: 1893:. This set can also be defined as 1784: 1634:all possible things that may exist 1570: 1548: 1500: 1450: 1428: 1398: 1316: 1273: 1209: 1143:{\displaystyle \{x\mid \Phi (x)\}} 1125: 1046: 1017:{\displaystyle \{x\mid \Phi (x)\}} 999: 776: 101:expressed in set-builder notation. 49: 25: 5964: 399:{\displaystyle \{1,2,3,\ldots \}} 27:Use of braces for specifying sets 5331: 4369:{\displaystyle \{l\ |\ l\in L\}} 4261: 3136:the set of all rational numbers. 2302:is greater than 0 and less than 1347:The ∈ symbol here denotes 3111:is the set of all integers, is 2507:{\displaystyle (\exists x)P(x)} 1294: 1288: 1067:{\displaystyle \{x:\Phi (x)\}.} 968:for an element of the set, and 759:{\displaystyle =\{1,\dots ,0\}} 5307: 5252: 5226: 5201: 5175: 5162: 5149: 5122: 4446: 4440: 4406: 4399: 4387: 4347: 4196: 4190: 4140: 4137: 4131: 4113: 4101: 4098: 4089: 4086: 4077: 4074: 4065: 3954: 3946: 3878: 3868: 3860: 3842: 3839: 3836: 3803: 3767: 3759: 3672: 3669: 3666: 3660: 3642: 3639: 3636: 3633: 3627: 3609: 3606: 3603: 3594: 3565: 3559: 3532: 3526: 3454: 3442: 3363: 3351: 3220: 3199: 2933: 2930: 2924: 2915: 2909: 2897: 2873: 2867: 2858: 2852: 2817: 2811: 2802: 2796: 2767: 2761: 2699: 2672: 2669: 2652: 2649: 2632: 2584: 2569: 2566: 2549: 2501: 2495: 2489: 2480: 2422: 2393: 2390: 2381: 2282: 2276: 2239: 2227: 1835: 1827: 1787: 1775: 1657: 1628:, as this would represent the 1585: 1579: 1563: 1557: 1509: 1503: 1465: 1459: 1443: 1437: 1407: 1401: 1381:that belong to some given set 1325: 1319: 1282: 1276: 1218: 1212: 1134: 1128: 1055: 1049: 1008: 1002: 729: 723: 677: 671: 657:{\displaystyle \{1,\dots ,n\}} 567:{\displaystyle \{1,\dots ,n\}} 13: 1: 3129:{\displaystyle \mathbb {Q} ,} 2514:is read as "there exists an 893:{\displaystyle 1\leq i\leq n} 619:{\displaystyle 1\leq i\leq n} 213:{\displaystyle \{7,3,15,31\}} 4305:The same can be achieved in 4250:operations over one or more 3104:{\displaystyle \mathbb {Z} } 3014:{\displaystyle \mathbb {N} } 1150:is the set of all values of 7: 5103: 4019:Zermelo–Fraenkel set theory 3678:{\displaystyle (\forall t)} 3187:is the set of odd integers. 1793:{\displaystyle (0,\infty )} 1757:is the set of all strictly 1702: 956:Sets defined by a predicate 690:. A subtle special case is 528:is the set of all integers. 159:Sets defined by enumeration 10: 5969: 5798:von Neumann–Bernays–Gödel 5168:Michael J Cullinan, 2012, 4219: 4023:set existence axiom scheme 3938:is a rational number with 2471:existential quantification 1764:, which can be written in 1640:shows that the expression 782:{\displaystyle \emptyset } 162: 5862: 5825: 5737: 5627: 5599:One-to-one correspondence 5515: 5456: 5340: 5329: 5315: 5260:"Sequence Comprehensions" 5159:, Brooks Cole, p. 6. 4845: 4775: 4681: 4578: 4559: 4465: 3377:{\displaystyle t=(u-1)/2} 1156:that satisfy the formula 927:addresses on Pine Street 5115: 5049: 5022: 5009: 5003: 4990: 4984: 4893: 4851: 4799: 4781: 4711: 4687: 4614: 4584: 4571: 4565: 4498: 4471: 4216:In programming languages 4002:{\displaystyle \{-1,1\}} 3303:. Make the substitution 1886:{\displaystyle \{-1,1\}} 1413:{\displaystyle \Phi (x)} 664:is the bracket notation 110:and its applications to 5129:Rosen, Kenneth (2007). 4025:, which states that if 3927:{\displaystyle x^{2}=1} 1692:In cases where the set 1170:satisfies the formula. 841:denotes the set of all 626:. Another notation for 149:or as defining a set's 5557:Constructible universe 5377:Constructibility (V=L) 5209:"Set-Builder Notation" 5110:Glossary of set theory 4456: 4370: 4206: 4150: 4003: 3968: 3928: 3888: 3784: 3679: 3575: 3483: 3378: 3332: 3331:{\displaystyle u=2t+1} 3297: 3244: 3181: 3130: 3105: 3083: 3015: 2993: 2943: 2830: 2777: 2709: 2594: 2508: 2459: 2458:{\displaystyle \land } 2432: 2349: 2292: 2209: 2143: 2054: 1940: 1887: 1852: 1794: 1751: 1683: 1615: 1614:{\displaystyle \land } 1595: 1519: 1472: 1414: 1365: 1364:{\displaystyle \land } 1338: 1231: 1144: 1068: 1018: 941: 921: 894: 862: 835: 783: 760: 710: 684: 658: 620: 588: 568: 522: 400: 354: 284:is the set containing 278: 214: 92: 85: 5953:Mathematical notation 5780:Principia Mathematica 5614:Transfinite induction 5473:(i.e. set difference) 5188:mathworld.wolfram.com 4457: 4371: 4228:programming languages 4207: 4151: 4004: 3969: 3967:{\displaystyle |x|=1} 3929: 3889: 3785: 3680: 3576: 3484: 3379: 3333: 3298: 3245: 3182: 3131: 3106: 3084: 3016: 2994: 2944: 2836:which should be read 2831: 2778: 2710: 2595: 2509: 2460: 2433: 2350: 2293: 2210: 2144: 2055: 1941: 1888: 1853: 1795: 1752: 1684: 1616: 1596: 1525:is sometimes written 1520: 1473: 1415: 1366: 1339: 1232: 1174:Specifying the domain 1145: 1069: 1019: 942: 922: 895: 863: 861:{\displaystyle a_{i}} 836: 784: 761: 711: 685: 659: 621: 589: 569: 523: 401: 355: 279: 215: 128:mathematical notation 86: 32: 5854:Burali-Forti paradox 5609:Set-builder notation 5562:Continuum hypothesis 5502:Symmetric difference 5090:monad comprehensions 4381: 4334: 4169: 4062: 3978: 3942: 3905: 3800: 3699: 3591: 3505: 3395: 3342: 3307: 3258: 3193: 3142: 3115: 3093: 3027: 3003: 2960: 2843: 2787: 2746: 2612: 2537: 2477: 2449: 2361: 2329: 2221: 2153: 2064: 1963: 1897: 1862: 1806: 1772: 1715: 1644: 1605: 1529: 1482: 1424: 1395: 1355: 1247: 1191: 1113: 1034: 987: 931: 911: 872: 845: 793: 773: 720: 694: 668: 630: 598: 578: 540: 416: 366: 314: 226: 180: 124:set-builder notation 37: 18:Set builder notation 5815:Tarski–Grothendieck 5235:"Russell's Paradox" 5182:Weisstein, Eric W. 4013:Set existence axiom 2467:logical conjunction 1626:domain of discourse 1389:Set existence axiom 1373:logical conjunction 709:{\displaystyle n=0} 134:by enumerating its 5404:Limitation of size 4452: 4366: 4276:List comprehension 4240:list comprehension 4222:List comprehension 4202: 4146: 3999: 3964: 3924: 3884: 3780: 3675: 3571: 3479: 3374: 3338:, which is to say 3328: 3293: 3240: 3177: 3126: 3101: 3079: 3011: 2989: 2939: 2826: 2773: 2705: 2590: 2504: 2473:. So for example, 2455: 2438:is the set of all 2428: 2345: 2288: 2205: 2139: 2050: 1936: 1883: 1848: 1790: 1747: 1679: 1611: 1591: 1515: 1468: 1410: 1361: 1334: 1227: 1140: 1089:is said to be the 1064: 1014: 940:{\displaystyle \}} 937: 920:{\displaystyle \{} 917: 890: 858: 831: 779: 756: 706: 680: 654: 616: 584: 564: 518: 396: 350: 274: 210: 81: 5935: 5934: 5844:Russell's paradox 5793:Zermelo–Fraenkel 5694:Dedekind-infinite 5567:Diagonal argument 5466:Cartesian product 5323:Set (mathematics) 5142:978-0-07-288008-3 5086: 5085: 4412: 4404: 4353: 4345: 4296: 4295: 4242:, which combines 2742:. So instead of 2324:cartesian product 2060:. As an example, 1953:For each integer 1766:interval notation 1663: 1655: 1638:Russell's paradox 1420:is a conjunction 1292: 1271: 1164:, if no value of 587:{\displaystyle i} 143:set comprehension 130:for describing a 16:(Redirected from 5960: 5917:Bertrand Russell 5907:John von Neumann 5892:Abraham Fraenkel 5887:Richard Dedekind 5849:Suslin's problem 5760:Cantor's theorem 5477:De Morgan's laws 5335: 5302: 5295: 5288: 5279: 5278: 5272: 5271: 5269: 5267: 5256: 5250: 5249: 5247: 5245: 5230: 5224: 5223: 5221: 5219: 5205: 5199: 5198: 5196: 5194: 5179: 5173: 5166: 5160: 5153: 5147: 5146: 5126: 5080: 5077: 5074: 5071: 5068: 5065: 5062: 5059: 5056: 5053: 5044: 5041: 5038: 5035: 5032: 5029: 5026: 4972: 4969: 4966: 4963: 4960: 4957: 4954: 4951: 4948: 4945: 4942: 4939: 4936: 4933: 4930: 4927: 4924: 4921: 4918: 4915: 4912: 4909: 4906: 4903: 4900: 4897: 4888: 4885: 4882: 4879: 4876: 4873: 4870: 4867: 4864: 4861: 4858: 4855: 4839: 4836: 4833: 4830: 4827: 4824: 4821: 4818: 4815: 4812: 4809: 4806: 4803: 4794: 4791: 4788: 4785: 4769: 4766: 4763: 4760: 4757: 4754: 4751: 4748: 4745: 4742: 4739: 4736: 4733: 4730: 4727: 4724: 4721: 4718: 4715: 4706: 4703: 4700: 4697: 4694: 4691: 4675: 4672: 4669: 4666: 4663: 4660: 4657: 4654: 4651: 4648: 4645: 4642: 4639: 4636: 4633: 4630: 4627: 4624: 4621: 4618: 4609: 4606: 4603: 4600: 4597: 4594: 4591: 4588: 4553: 4550: 4547: 4544: 4541: 4538: 4535: 4532: 4529: 4526: 4523: 4520: 4517: 4514: 4511: 4508: 4505: 4502: 4493: 4490: 4487: 4484: 4481: 4478: 4475: 4461: 4459: 4458: 4453: 4410: 4409: 4402: 4375: 4373: 4372: 4367: 4351: 4350: 4343: 4315: 4314: 4291: 4288: 4265: 4264: 4257: 4211: 4209: 4208: 4203: 4164: 4155: 4153: 4152: 4147: 4054: 4050: 4044: 4038: 4030: 4008: 4006: 4005: 4000: 3973: 3971: 3970: 3965: 3957: 3949: 3933: 3931: 3930: 3925: 3917: 3916: 3893: 3891: 3890: 3885: 3871: 3863: 3855: 3829: 3828: 3816: 3789: 3787: 3786: 3781: 3770: 3762: 3754: 3728: 3727: 3715: 3684: 3682: 3681: 3676: 3584:if and only if 3580: 3578: 3577: 3572: 3488: 3486: 3485: 3480: 3472: 3461: 3426: 3383: 3381: 3380: 3375: 3370: 3337: 3335: 3334: 3329: 3302: 3300: 3299: 3294: 3289: 3249: 3247: 3246: 3241: 3236: 3186: 3184: 3183: 3178: 3173: 3135: 3133: 3132: 3127: 3122: 3110: 3108: 3107: 3102: 3100: 3088: 3086: 3085: 3080: 3063: 3040: 3020: 3018: 3017: 3012: 3010: 2998: 2996: 2995: 2990: 2985: 2948: 2946: 2945: 2940: 2835: 2833: 2832: 2827: 2782: 2780: 2779: 2774: 2737: 2717:rational numbers 2714: 2712: 2711: 2706: 2668: 2648: 2628: 2605: 2599: 2597: 2596: 2591: 2565: 2530: 2519: 2513: 2511: 2510: 2505: 2464: 2462: 2461: 2456: 2437: 2435: 2434: 2429: 2406: 2377: 2354: 2352: 2351: 2346: 2344: 2336: 2321: 2312: 2297: 2295: 2294: 2289: 2257: 2249: 2214: 2212: 2211: 2206: 2168: 2167: 2148: 2146: 2145: 2140: 2093: 2076: 2075: 2059: 2057: 2056: 2051: 1992: 1975: 1974: 1959:, we can define 1958: 1945: 1943: 1942: 1937: 1926: 1925: 1913: 1892: 1890: 1889: 1884: 1857: 1855: 1854: 1849: 1838: 1830: 1822: 1799: 1797: 1796: 1791: 1756: 1754: 1753: 1748: 1731: 1697: 1688: 1686: 1685: 1680: 1661: 1660: 1653: 1620: 1618: 1617: 1612: 1600: 1598: 1597: 1592: 1578: 1577: 1556: 1555: 1524: 1522: 1521: 1516: 1477: 1475: 1474: 1469: 1458: 1457: 1436: 1435: 1419: 1417: 1416: 1411: 1386: 1380: 1370: 1368: 1367: 1362: 1343: 1341: 1340: 1335: 1293: 1290: 1272: 1269: 1236: 1234: 1233: 1228: 1183: 1169: 1160:. It may be the 1159: 1155: 1149: 1147: 1146: 1141: 1108: 1102: 1097:. All values of 1088: 1073: 1071: 1070: 1065: 1023: 1021: 1020: 1015: 946: 944: 943: 938: 926: 924: 923: 918: 899: 897: 896: 891: 867: 865: 864: 859: 857: 856: 840: 838: 837: 832: 827: 826: 808: 807: 788: 786: 785: 780: 766:is equal to the 765: 763: 762: 757: 715: 713: 712: 707: 689: 687: 686: 683:{\displaystyle } 681: 663: 661: 660: 655: 625: 623: 622: 617: 593: 591: 590: 585: 573: 571: 570: 565: 527: 525: 524: 519: 405: 403: 402: 397: 359: 357: 356: 351: 295: 291: 287: 283: 281: 280: 275: 219: 217: 216: 211: 120:computer science 102: 90: 88: 87: 82: 62: 21: 5968: 5967: 5963: 5962: 5961: 5959: 5958: 5957: 5938: 5937: 5936: 5931: 5858: 5837: 5821: 5786:New Foundations 5733: 5623: 5542:Cardinal number 5525: 5511: 5452: 5336: 5327: 5311: 5306: 5276: 5275: 5265: 5263: 5258: 5257: 5253: 5243: 5241: 5231: 5227: 5217: 5215: 5207: 5206: 5202: 5192: 5190: 5180: 5176: 5167: 5163: 5154: 5150: 5143: 5127: 5123: 5118: 5106: 5082: 5081: 5078: 5075: 5072: 5069: 5066: 5063: 5060: 5057: 5054: 5051: 5046: 5045: 5042: 5039: 5036: 5033: 5030: 5027: 5024: 5012: 5011: 5006: 5005: 4993: 4992: 4987: 4986: 4974: 4973: 4970: 4967: 4964: 4961: 4958: 4955: 4952: 4949: 4946: 4943: 4940: 4937: 4934: 4931: 4928: 4925: 4922: 4919: 4916: 4913: 4910: 4907: 4904: 4901: 4898: 4895: 4890: 4889: 4886: 4883: 4880: 4877: 4874: 4871: 4868: 4865: 4862: 4859: 4856: 4853: 4841: 4840: 4837: 4834: 4831: 4828: 4825: 4822: 4819: 4816: 4813: 4810: 4807: 4804: 4801: 4796: 4795: 4792: 4789: 4786: 4783: 4771: 4770: 4767: 4764: 4761: 4758: 4755: 4752: 4749: 4746: 4743: 4740: 4737: 4734: 4731: 4728: 4725: 4722: 4719: 4716: 4713: 4708: 4707: 4704: 4701: 4698: 4695: 4692: 4689: 4677: 4676: 4673: 4670: 4667: 4664: 4661: 4658: 4655: 4652: 4649: 4646: 4643: 4640: 4637: 4634: 4631: 4628: 4625: 4622: 4619: 4616: 4611: 4610: 4607: 4604: 4601: 4598: 4595: 4592: 4589: 4586: 4574: 4573: 4568: 4567: 4555: 4554: 4551: 4548: 4545: 4542: 4539: 4536: 4533: 4530: 4527: 4524: 4521: 4518: 4515: 4512: 4509: 4506: 4503: 4500: 4495: 4494: 4491: 4488: 4485: 4482: 4479: 4476: 4473: 4405: 4382: 4379: 4378: 4346: 4335: 4332: 4331: 4292: 4286: 4283: 4266: 4262: 4224: 4218: 4170: 4167: 4166: 4160: 4063: 4060: 4059: 4052: 4046: 4040: 4032: 4026: 4015: 3979: 3976: 3975: 3953: 3945: 3943: 3940: 3939: 3934:if and only if 3912: 3908: 3906: 3903: 3902: 3867: 3859: 3851: 3824: 3820: 3812: 3801: 3798: 3797: 3766: 3758: 3750: 3723: 3719: 3711: 3700: 3697: 3696: 3592: 3589: 3588: 3506: 3503: 3502: 3495: 3468: 3457: 3422: 3396: 3393: 3392: 3384:, then replace 3366: 3343: 3340: 3339: 3308: 3305: 3304: 3285: 3259: 3256: 3255: 3232: 3194: 3191: 3190: 3169: 3143: 3140: 3139: 3118: 3116: 3113: 3112: 3096: 3094: 3091: 3090: 3059: 3036: 3028: 3025: 3024: 3006: 3004: 3001: 3000: 2981: 2961: 2958: 2957: 2844: 2841: 2840: 2788: 2785: 2784: 2747: 2744: 2743: 2733: 2730: 2664: 2644: 2624: 2613: 2610: 2609: 2601: 2561: 2538: 2535: 2534: 2521: 2515: 2478: 2475: 2474: 2450: 2447: 2446: 2443:natural numbers 2402: 2373: 2362: 2359: 2358: 2340: 2332: 2330: 2327: 2326: 2317: 2303: 2253: 2245: 2222: 2219: 2218: 2160: 2156: 2154: 2151: 2150: 2089: 2071: 2067: 2065: 2062: 2061: 1988: 1970: 1966: 1964: 1961: 1960: 1954: 1921: 1917: 1909: 1898: 1895: 1894: 1863: 1860: 1859: 1834: 1826: 1818: 1807: 1804: 1803: 1773: 1770: 1769: 1727: 1716: 1713: 1712: 1705: 1693: 1656: 1645: 1642: 1641: 1606: 1603: 1602: 1573: 1569: 1551: 1547: 1530: 1527: 1526: 1483: 1480: 1479: 1453: 1449: 1431: 1427: 1425: 1422: 1421: 1396: 1393: 1392: 1382: 1376: 1356: 1353: 1352: 1289: 1270: and  1268: 1248: 1245: 1244: 1192: 1189: 1188: 1179: 1176: 1165: 1157: 1151: 1114: 1111: 1110: 1104: 1098: 1082: 1035: 1032: 1031: 988: 985: 984: 958: 932: 929: 928: 912: 909: 908: 873: 870: 869: 852: 848: 846: 843: 842: 822: 818: 803: 799: 794: 791: 790: 774: 771: 770: 721: 718: 717: 695: 692: 691: 669: 666: 665: 631: 628: 627: 599: 596: 595: 579: 576: 575: 541: 538: 537: 417: 414: 413: 408:natural numbers 367: 364: 363: 315: 312: 311: 293: 289: 285: 227: 224: 223: 181: 178: 177: 167: 161: 147:set abstraction 104: 100: 95:The set of all 94: 58: 38: 35: 34: 28: 23: 22: 15: 12: 11: 5: 5966: 5956: 5955: 5950: 5933: 5932: 5930: 5929: 5924: 5922:Thoralf Skolem 5919: 5914: 5909: 5904: 5899: 5894: 5889: 5884: 5879: 5874: 5868: 5866: 5860: 5859: 5857: 5856: 5851: 5846: 5840: 5838: 5836: 5835: 5832: 5826: 5823: 5822: 5820: 5819: 5818: 5817: 5812: 5807: 5806: 5805: 5790: 5789: 5788: 5776: 5775: 5774: 5763: 5762: 5757: 5752: 5747: 5741: 5739: 5735: 5734: 5732: 5731: 5726: 5721: 5716: 5707: 5702: 5697: 5687: 5682: 5681: 5680: 5675: 5670: 5660: 5650: 5645: 5640: 5634: 5632: 5625: 5624: 5622: 5621: 5616: 5611: 5606: 5604:Ordinal number 5601: 5596: 5591: 5586: 5585: 5584: 5579: 5569: 5564: 5559: 5554: 5549: 5539: 5534: 5528: 5526: 5524: 5523: 5520: 5516: 5513: 5512: 5510: 5509: 5504: 5499: 5494: 5489: 5484: 5482:Disjoint union 5479: 5474: 5468: 5462: 5460: 5454: 5453: 5451: 5450: 5449: 5448: 5443: 5432: 5431: 5429:Martin's axiom 5426: 5421: 5416: 5411: 5406: 5401: 5396: 5394:Extensionality 5391: 5390: 5389: 5379: 5374: 5373: 5372: 5367: 5362: 5352: 5346: 5344: 5338: 5337: 5330: 5328: 5326: 5325: 5319: 5317: 5313: 5312: 5305: 5304: 5297: 5290: 5282: 5274: 5273: 5251: 5225: 5213:mathsisfun.com 5200: 5174: 5161: 5148: 5141: 5120: 5119: 5117: 5114: 5113: 5112: 5105: 5102: 5084: 5083: 5050: 5047: 5023: 5020: 5014: 5013: 5010: 5007: 5004: 5001: 4995: 4994: 4991: 4988: 4985: 4982: 4976: 4975: 4894: 4891: 4852: 4849: 4843: 4842: 4800: 4797: 4782: 4779: 4773: 4772: 4712: 4709: 4688: 4685: 4679: 4678: 4615: 4612: 4585: 4582: 4576: 4575: 4572: 4569: 4566: 4563: 4557: 4556: 4499: 4496: 4472: 4469: 4463: 4462: 4451: 4448: 4445: 4442: 4439: 4436: 4433: 4430: 4427: 4424: 4421: 4418: 4415: 4408: 4401: 4398: 4395: 4392: 4389: 4386: 4376: 4365: 4362: 4359: 4356: 4349: 4342: 4339: 4329: 4325: 4324: 4321: 4318: 4294: 4293: 4269: 4267: 4260: 4220:Main article: 4217: 4214: 4201: 4198: 4195: 4192: 4189: 4186: 4183: 4180: 4177: 4174: 4157: 4156: 4145: 4142: 4139: 4136: 4133: 4130: 4127: 4124: 4121: 4118: 4115: 4112: 4109: 4106: 4103: 4100: 4097: 4094: 4091: 4088: 4085: 4082: 4079: 4076: 4073: 4070: 4067: 4014: 4011: 3998: 3995: 3992: 3989: 3986: 3983: 3963: 3960: 3956: 3952: 3948: 3923: 3920: 3915: 3911: 3895: 3894: 3883: 3880: 3877: 3874: 3870: 3866: 3862: 3858: 3854: 3850: 3847: 3844: 3841: 3838: 3835: 3832: 3827: 3823: 3819: 3815: 3811: 3808: 3805: 3791: 3790: 3779: 3776: 3773: 3769: 3765: 3761: 3757: 3753: 3749: 3746: 3743: 3740: 3737: 3734: 3731: 3726: 3722: 3718: 3714: 3710: 3707: 3704: 3687: 3686: 3674: 3671: 3668: 3665: 3662: 3659: 3656: 3653: 3650: 3647: 3644: 3641: 3638: 3635: 3632: 3629: 3626: 3623: 3620: 3617: 3614: 3611: 3608: 3605: 3602: 3599: 3596: 3582: 3581: 3570: 3567: 3564: 3561: 3558: 3555: 3552: 3549: 3546: 3543: 3540: 3537: 3534: 3531: 3528: 3525: 3522: 3519: 3516: 3513: 3510: 3494: 3491: 3490: 3489: 3478: 3475: 3471: 3467: 3464: 3460: 3456: 3453: 3450: 3447: 3444: 3441: 3438: 3435: 3432: 3429: 3425: 3421: 3418: 3415: 3412: 3409: 3406: 3403: 3400: 3373: 3369: 3365: 3362: 3359: 3356: 3353: 3350: 3347: 3327: 3324: 3321: 3318: 3315: 3312: 3292: 3288: 3284: 3281: 3278: 3275: 3272: 3269: 3266: 3263: 3252: 3251: 3239: 3235: 3231: 3228: 3225: 3222: 3219: 3216: 3213: 3210: 3207: 3204: 3201: 3198: 3188: 3176: 3172: 3168: 3165: 3162: 3159: 3156: 3153: 3150: 3147: 3137: 3125: 3121: 3099: 3078: 3075: 3072: 3069: 3066: 3062: 3058: 3055: 3052: 3049: 3046: 3043: 3039: 3035: 3032: 3022: 3009: 2988: 2984: 2980: 2977: 2974: 2971: 2968: 2965: 2951: 2950: 2938: 2935: 2932: 2929: 2926: 2923: 2920: 2917: 2914: 2911: 2908: 2905: 2902: 2899: 2896: 2893: 2890: 2887: 2884: 2881: 2878: 2875: 2872: 2869: 2866: 2863: 2860: 2857: 2854: 2851: 2848: 2825: 2822: 2819: 2816: 2813: 2810: 2807: 2804: 2801: 2798: 2795: 2792: 2783:, we may have 2772: 2769: 2766: 2763: 2760: 2757: 2754: 2751: 2729: 2726: 2725: 2724: 2715:is the set of 2704: 2701: 2698: 2695: 2692: 2689: 2686: 2683: 2680: 2677: 2674: 2671: 2667: 2663: 2660: 2657: 2654: 2651: 2647: 2643: 2640: 2637: 2634: 2631: 2627: 2623: 2620: 2617: 2607: 2589: 2586: 2583: 2580: 2577: 2574: 2571: 2568: 2564: 2560: 2557: 2554: 2551: 2548: 2545: 2542: 2532: 2503: 2500: 2497: 2494: 2491: 2488: 2485: 2482: 2454: 2427: 2424: 2421: 2418: 2415: 2412: 2409: 2405: 2401: 2398: 2395: 2392: 2389: 2386: 2383: 2380: 2376: 2372: 2369: 2366: 2356: 2343: 2339: 2335: 2313:, for a given 2287: 2284: 2281: 2278: 2275: 2272: 2269: 2266: 2263: 2260: 2256: 2252: 2248: 2244: 2241: 2238: 2235: 2232: 2229: 2226: 2216: 2204: 2201: 2198: 2195: 2192: 2189: 2186: 2183: 2180: 2177: 2174: 2171: 2166: 2163: 2159: 2138: 2135: 2132: 2129: 2126: 2123: 2120: 2117: 2114: 2111: 2108: 2105: 2102: 2099: 2096: 2092: 2088: 2085: 2082: 2079: 2074: 2070: 2049: 2046: 2043: 2040: 2037: 2034: 2031: 2028: 2025: 2022: 2019: 2016: 2013: 2010: 2007: 2004: 2001: 1998: 1995: 1991: 1987: 1984: 1981: 1978: 1973: 1969: 1951: 1935: 1932: 1929: 1924: 1920: 1916: 1912: 1908: 1905: 1902: 1882: 1879: 1876: 1873: 1870: 1867: 1847: 1844: 1841: 1837: 1833: 1829: 1825: 1821: 1817: 1814: 1811: 1801: 1789: 1786: 1783: 1780: 1777: 1746: 1743: 1740: 1737: 1734: 1730: 1726: 1723: 1720: 1704: 1701: 1678: 1675: 1672: 1669: 1666: 1659: 1652: 1649: 1610: 1590: 1587: 1584: 1581: 1576: 1572: 1568: 1565: 1562: 1559: 1554: 1550: 1546: 1543: 1540: 1537: 1534: 1514: 1511: 1508: 1505: 1502: 1499: 1496: 1493: 1490: 1487: 1467: 1464: 1461: 1456: 1452: 1448: 1445: 1442: 1439: 1434: 1430: 1409: 1406: 1403: 1400: 1360: 1349:set membership 1345: 1344: 1333: 1330: 1327: 1324: 1321: 1318: 1315: 1312: 1309: 1306: 1303: 1300: 1297: 1287: 1284: 1281: 1278: 1275: 1267: 1264: 1261: 1258: 1255: 1252: 1238: 1237: 1226: 1223: 1220: 1217: 1214: 1211: 1208: 1205: 1202: 1199: 1196: 1175: 1172: 1139: 1136: 1133: 1130: 1127: 1124: 1121: 1118: 1075: 1074: 1063: 1060: 1057: 1054: 1051: 1048: 1045: 1042: 1039: 1025: 1024: 1013: 1010: 1007: 1004: 1001: 998: 995: 992: 957: 954: 949: 948: 936: 916: 889: 886: 883: 880: 877: 855: 851: 830: 825: 821: 817: 814: 811: 806: 802: 798: 778: 755: 752: 749: 746: 743: 740: 737: 734: 731: 728: 725: 705: 702: 699: 679: 676: 673: 653: 650: 647: 644: 641: 638: 635: 615: 612: 609: 606: 603: 583: 563: 560: 557: 554: 551: 548: 545: 530: 529: 517: 514: 511: 508: 505: 502: 499: 496: 493: 490: 487: 484: 481: 478: 475: 472: 469: 466: 463: 460: 457: 454: 451: 448: 445: 442: 439: 436: 433: 430: 427: 424: 421: 411: 406:is the set of 395: 392: 389: 386: 383: 380: 377: 374: 371: 361: 349: 346: 343: 340: 337: 334: 331: 328: 325: 322: 319: 298: 297: 273: 270: 267: 264: 261: 258: 255: 252: 249: 246: 243: 240: 237: 234: 231: 221: 209: 206: 203: 200: 197: 194: 191: 188: 185: 163:Main article: 160: 157: 80: 77: 74: 71: 68: 65: 61: 57: 54: 51: 48: 45: 42: 31: 26: 9: 6: 4: 3: 2: 5965: 5954: 5951: 5949: 5946: 5945: 5943: 5928: 5927:Ernst Zermelo 5925: 5923: 5920: 5918: 5915: 5913: 5912:Willard Quine 5910: 5908: 5905: 5903: 5900: 5898: 5895: 5893: 5890: 5888: 5885: 5883: 5880: 5878: 5875: 5873: 5870: 5869: 5867: 5865: 5864:Set theorists 5861: 5855: 5852: 5850: 5847: 5845: 5842: 5841: 5839: 5833: 5831: 5828: 5827: 5824: 5816: 5813: 5811: 5810:Kripke–Platek 5808: 5804: 5801: 5800: 5799: 5796: 5795: 5794: 5791: 5787: 5784: 5783: 5782: 5781: 5777: 5773: 5770: 5769: 5768: 5765: 5764: 5761: 5758: 5756: 5753: 5751: 5748: 5746: 5743: 5742: 5740: 5736: 5730: 5727: 5725: 5722: 5720: 5717: 5715: 5713: 5708: 5706: 5703: 5701: 5698: 5695: 5691: 5688: 5686: 5683: 5679: 5676: 5674: 5671: 5669: 5666: 5665: 5664: 5661: 5658: 5654: 5651: 5649: 5646: 5644: 5641: 5639: 5636: 5635: 5633: 5630: 5626: 5620: 5617: 5615: 5612: 5610: 5607: 5605: 5602: 5600: 5597: 5595: 5592: 5590: 5587: 5583: 5580: 5578: 5575: 5574: 5573: 5570: 5568: 5565: 5563: 5560: 5558: 5555: 5553: 5550: 5547: 5543: 5540: 5538: 5535: 5533: 5530: 5529: 5527: 5521: 5518: 5517: 5514: 5508: 5505: 5503: 5500: 5498: 5495: 5493: 5490: 5488: 5485: 5483: 5480: 5478: 5475: 5472: 5469: 5467: 5464: 5463: 5461: 5459: 5455: 5447: 5446:specification 5444: 5442: 5439: 5438: 5437: 5434: 5433: 5430: 5427: 5425: 5422: 5420: 5417: 5415: 5412: 5410: 5407: 5405: 5402: 5400: 5397: 5395: 5392: 5388: 5385: 5384: 5383: 5380: 5378: 5375: 5371: 5368: 5366: 5363: 5361: 5358: 5357: 5356: 5353: 5351: 5348: 5347: 5345: 5343: 5339: 5334: 5324: 5321: 5320: 5318: 5314: 5310: 5303: 5298: 5296: 5291: 5289: 5284: 5283: 5280: 5261: 5255: 5240: 5236: 5229: 5214: 5210: 5204: 5189: 5185: 5178: 5171: 5165: 5158: 5152: 5144: 5138: 5134: 5133: 5125: 5121: 5111: 5108: 5107: 5101: 5099: 5095: 5091: 5048: 5021: 5019: 5016: 5015: 5008: 5002: 5000: 4997: 4996: 4989: 4983: 4981: 4978: 4977: 4892: 4850: 4848: 4844: 4798: 4780: 4778: 4774: 4710: 4686: 4684: 4680: 4613: 4583: 4581: 4577: 4570: 4564: 4562: 4558: 4497: 4470: 4468: 4464: 4443: 4437: 4434: 4431: 4428: 4425: 4422: 4419: 4416: 4413: 4396: 4393: 4390: 4377: 4360: 4357: 4354: 4340: 4330: 4327: 4326: 4322: 4319: 4317: 4316: 4313: 4310: 4308: 4303: 4301: 4290: 4287:December 2023 4281: 4277: 4273: 4268: 4259: 4258: 4255: 4253: 4249: 4245: 4241: 4237: 4233: 4229: 4223: 4213: 4193: 4184: 4181: 4178: 4175: 4163: 4143: 4134: 4125: 4122: 4119: 4116: 4110: 4107: 4104: 4095: 4083: 4071: 4058: 4057: 4056: 4051:that satisfy 4049: 4043: 4036: 4031:is a set and 4029: 4024: 4020: 4010: 3993: 3990: 3987: 3984: 3961: 3958: 3950: 3937: 3921: 3918: 3913: 3909: 3900: 3881: 3875: 3872: 3864: 3856: 3848: 3845: 3833: 3830: 3825: 3821: 3817: 3809: 3806: 3796: 3795: 3794: 3774: 3771: 3763: 3755: 3747: 3744: 3738: 3732: 3729: 3724: 3720: 3716: 3708: 3705: 3695: 3694: 3693: 3692:For example, 3690: 3663: 3657: 3654: 3651: 3648: 3645: 3630: 3624: 3621: 3618: 3615: 3612: 3600: 3587: 3586: 3585: 3562: 3556: 3553: 3550: 3547: 3544: 3538: 3529: 3523: 3520: 3517: 3514: 3511: 3501: 3500: 3499: 3476: 3465: 3462: 3458: 3451: 3448: 3445: 3439: 3436: 3430: 3419: 3416: 3413: 3410: 3407: 3404: 3401: 3391: 3390: 3389: 3387: 3371: 3367: 3360: 3357: 3354: 3348: 3345: 3325: 3322: 3319: 3316: 3313: 3310: 3282: 3279: 3276: 3273: 3270: 3267: 3264: 3229: 3226: 3223: 3217: 3214: 3211: 3208: 3205: 3202: 3189: 3166: 3163: 3160: 3157: 3154: 3151: 3148: 3138: 3123: 3073: 3070: 3067: 3064: 3056: 3053: 3050: 3047: 3044: 3041: 3037: 3033: 3023: 2978: 2975: 2972: 2969: 2966: 2956: 2955: 2954: 2953:For example: 2927: 2918: 2912: 2906: 2903: 2900: 2894: 2888: 2885: 2879: 2870: 2861: 2855: 2849: 2839: 2838: 2837: 2823: 2814: 2805: 2799: 2793: 2764: 2755: 2752: 2741: 2736: 2722: 2718: 2696: 2693: 2690: 2687: 2684: 2681: 2678: 2675: 2661: 2658: 2641: 2638: 2629: 2621: 2618: 2608: 2604: 2581: 2578: 2575: 2572: 2558: 2555: 2546: 2543: 2533: 2528: 2524: 2518: 2498: 2492: 2486: 2472: 2468: 2452: 2444: 2441: 2419: 2416: 2413: 2410: 2407: 2399: 2396: 2387: 2378: 2370: 2367: 2357: 2337: 2325: 2322:. Here the 2320: 2316: 2310: 2306: 2301: 2279: 2273: 2270: 2267: 2264: 2261: 2258: 2250: 2242: 2236: 2233: 2230: 2217: 2199: 2196: 2193: 2190: 2187: 2184: 2181: 2178: 2175: 2169: 2164: 2161: 2157: 2133: 2130: 2127: 2124: 2121: 2118: 2115: 2109: 2103: 2100: 2097: 2094: 2086: 2083: 2077: 2072: 2068: 2044: 2041: 2038: 2035: 2032: 2029: 2026: 2023: 2020: 2017: 2014: 2008: 2002: 1999: 1996: 1993: 1985: 1982: 1976: 1971: 1967: 1957: 1952: 1949: 1930: 1927: 1922: 1918: 1914: 1906: 1903: 1877: 1874: 1871: 1868: 1842: 1839: 1831: 1823: 1815: 1812: 1802: 1781: 1778: 1767: 1763: 1760: 1741: 1738: 1735: 1732: 1724: 1721: 1711: 1710: 1709: 1700: 1696: 1690: 1676: 1670: 1667: 1664: 1650: 1639: 1635: 1631: 1627: 1622: 1608: 1582: 1574: 1566: 1560: 1552: 1544: 1541: 1538: 1535: 1506: 1497: 1494: 1491: 1488: 1462: 1454: 1446: 1440: 1432: 1404: 1391:" below). If 1390: 1385: 1379: 1374: 1358: 1350: 1331: 1322: 1313: 1310: 1307: 1304: 1301: 1298: 1279: 1265: 1262: 1259: 1256: 1253: 1243: 1242: 1241: 1224: 1215: 1206: 1203: 1200: 1197: 1187: 1186: 1185: 1182: 1171: 1168: 1163: 1154: 1131: 1122: 1119: 1107: 1101: 1096: 1092: 1086: 1080: 1061: 1052: 1043: 1040: 1030: 1029: 1028: 1005: 996: 993: 983: 982: 981: 979: 975: 971: 967: 963: 953: 907: 906: 905: 901: 887: 884: 881: 878: 875: 853: 849: 823: 819: 815: 812: 809: 804: 800: 789:. Similarly, 769: 750: 747: 744: 741: 738: 732: 726: 703: 700: 697: 674: 648: 645: 642: 639: 636: 613: 610: 607: 604: 601: 581: 558: 555: 552: 549: 546: 534: 512: 509: 506: 503: 500: 497: 494: 491: 488: 485: 482: 479: 476: 470: 464: 461: 458: 455: 452: 449: 446: 443: 440: 437: 434: 431: 428: 425: 422: 412: 409: 390: 387: 384: 381: 378: 375: 372: 362: 344: 341: 338: 335: 332: 329: 326: 323: 320: 310: 309: 308: 306: 301: 268: 265: 262: 259: 256: 250: 244: 241: 238: 235: 232: 222: 204: 201: 198: 195: 192: 189: 186: 176: 175: 174: 172: 166: 156: 154: 153: 148: 144: 139: 137: 133: 129: 125: 121: 117: 113: 109: 103: 98: 97:even integers 91: 75: 72: 69: 66: 63: 55: 52: 46: 43: 30: 19: 5877:Georg Cantor 5872:Paul Bernays 5803:Morse–Kelley 5778: 5711: 5710:Subset  5657:hereditarily 5619:Venn diagram 5608: 5577:ordered pair 5492:Intersection 5436:Axiom schema 5264:. Retrieved 5254: 5242:. Retrieved 5238: 5228: 5216:. Retrieved 5212: 5203: 5191:. Retrieved 5187: 5177: 5169: 5164: 5156: 5151: 5131: 5124: 5098:zero element 5089: 5087: 4328:Set-builder 4311: 4304: 4297: 4284: 4225: 4161: 4158: 4047: 4041: 4034: 4027: 4016: 3935: 3898: 3896: 3792: 3691: 3688: 3583: 3496: 3385: 3253: 2952: 2734: 2731: 2602: 2526: 2522: 2516: 2318: 2308: 2304: 2299: 1955: 1762:real numbers 1706: 1694: 1691: 1633: 1623: 1383: 1377: 1351:, while the 1346: 1239: 1180: 1177: 1166: 1152: 1105: 1099: 1094: 1090: 1084: 1078: 1076: 1026: 978:vertical bar 969: 965: 959: 950: 902: 536:In general, 535: 531: 302: 299: 168: 150: 146: 142: 140: 123: 105: 93: 33: 29: 5902:Thomas Jech 5745:Alternative 5724:Uncountable 5678:Ultrafilter 5537:Cardinality 5441:replacement 5382:Determinacy 5018:Mathematica 1858:is the set 716:, in which 116:mathematics 5948:Set theory 5942:Categories 5897:Kurt Gödel 5882:Paul Cohen 5719:Transitive 5487:Identities 5471:Complement 5458:Operations 5419:Regularity 5387:projective 5350:Adjunction 5309:Set theory 4323:Example 2 3901:, we have 2740:expression 2520:such that 594:such that 108:set theory 5830:Paradoxes 5750:Axiomatic 5729:Universal 5705:Singleton 5700:Recursive 5643:Countable 5638:Amorphous 5497:Power set 5414:Power set 5365:dependent 5360:countable 5218:20 August 5193:20 August 4435:∧ 4429:∈ 4423:∧ 4417:∈ 4358:∈ 4320:Example 1 4300:generator 4238:) is the 4230:(notably 4188:Φ 4185:∣ 4179:∈ 4129:Φ 4126:∧ 4120:∈ 4114:⇔ 4108:∈ 4093:∀ 4081:∃ 4069:∀ 3985:− 3857:∧ 3849:∈ 3840:⇔ 3818:∧ 3810:∈ 3756:∣ 3748:∈ 3717:∣ 3709:∈ 3655:∧ 3649:∈ 3640:⇔ 3622:∧ 3616:∈ 3598:∀ 3554:∣ 3548:∈ 3521:∣ 3515:∈ 3466:∈ 3449:− 3440:∣ 3420:∈ 3414:∣ 3358:− 3283:∈ 3277:∣ 3230:∈ 3224:∣ 3167:∈ 3161:∣ 3057:∈ 3045:∣ 2979:∈ 2973:∣ 2922:Φ 2919:∧ 2892:∃ 2889:∣ 2865:Φ 2862:∣ 2809:Φ 2806:∣ 2759:Φ 2756:∣ 2685:∧ 2662:∈ 2656:∃ 2642:∈ 2636:∃ 2630:∣ 2622:∈ 2559:∈ 2553:∃ 2547:∣ 2484:∃ 2453:∧ 2408:∧ 2400:∈ 2385:∃ 2379:∣ 2371:∈ 2338:× 2259:∣ 2251:× 2243:∈ 2200:… 2185:− 2176:− 2162:− 2134:… 2101:≥ 2095:∣ 2087:∈ 2045:… 2000:≥ 1994:∣ 1986:∈ 1915:∣ 1907:∈ 1869:− 1824:∣ 1816:∈ 1785:∞ 1733:∣ 1725:∈ 1609:∧ 1571:Φ 1549:Φ 1545:∣ 1539:∈ 1501:Φ 1498:∣ 1492:∈ 1451:Φ 1447:∧ 1429:Φ 1399:Φ 1359:∧ 1317:Φ 1314:∧ 1308:∈ 1302:∣ 1274:Φ 1263:∈ 1257:∣ 1210:Φ 1207:∣ 1201:∈ 1178:A domain 1162:empty set 1126:Φ 1123:∣ 1095:predicate 1079:such that 1047:Φ 1000:Φ 997:∣ 962:predicate 885:≤ 879:≤ 813:… 777:∅ 768:empty set 745:… 643:… 611:≤ 605:≤ 553:… 513:… 504:− 489:− 465:… 438:− 429:− 423:… 391:… 339:… 152:intension 56:∈ 50:∃ 47:∣ 5834:Problems 5738:Theories 5714:Superset 5690:Infinite 5519:Concepts 5399:Infinity 5316:Overview 5266:6 August 5244:6 August 5104:See also 4159:The set 3089:, where 3071:≠ 2999:, where 2738:with an 2721:integers 2679:≠ 2315:function 1759:positive 1703:Examples 1668:∉ 305:ellipsis 136:elements 5772:General 5767:Zermelo 5673:subbase 5655: ( 5594:Forcing 5572:Element 5544: ( 5522:Methods 5409:Pairing 5262:. Scala 5096:with a 4561:Haskell 4280:Discuss 4236:Haskell 1478:, then 1093:or the 1083:Φ( 5663:Filter 5653:Finite 5589:Family 5532:Almost 5370:global 5355:Choice 5342:Axioms 5139:  5031:|-> 4980:Erlang 4968:Result 4932:member 4914:member 4884:Result 4866:member 4847:Prolog 4802:SELECT 4784:SELECT 4753:select 4702:select 4467:Python 4411:  4403:  4352:  4344:  4248:filter 4232:Python 2445:. The 1950:below. 1946:; see 1662:  1654:  1630:subset 1158:Φ 292:, and 118:, and 5755:Naive 5685:Fuzzy 5648:Empty 5631:types 5582:tuple 5552:Class 5546:large 5507:Union 5424:Union 5184:"Set" 5116:Notes 5094:monad 5052:Cases 4999:Julia 4896:setof 4854:setof 4826:WHERE 4823:X_set 4817:K_set 4793:L_set 4738:where 4659:yield 4638:<- 4626:<- 4605:yield 4596:<- 4580:Scala 4307:Scala 4274:into 4272:moved 4252:lists 974:colon 970:false 126:is a 112:logic 5668:base 5268:2017 5246:2017 5220:2020 5195:2020 5137:ISBN 4950:call 4814:FROM 4790:FROM 4726:from 4714:from 4690:from 4246:and 4234:and 2440:even 2271:< 2265:< 2149:and 1739:> 1091:rule 966:true 868:for 5629:Set 4965:)), 4911:),( 4777:SQL 4617:for 4587:for 4528:for 4516:for 4480:for 4282:) 4278:. ( 4244:map 1768:as 1632:of 1027:or 976:or 345:100 171:set 132:set 106:In 5944:: 5237:. 5211:. 5186:. 5100:. 5073:/; 5067:x_ 5061:k_ 5040:/@ 4947:), 4944:Xs 4929:), 4926:Ks 4899:(( 4881:), 4878:Ls 4732:in 4720:in 4696:in 4683:C# 4656:)) 4644:if 4552:)} 4540:if 4534:in 4522:in 4501:{( 4486:in 4254:. 4212:. 4055:: 4033:Φ( 4009:. 2531:". 1621:. 1291:or 900:. 288:, 205:31 199:15 169:A 155:. 145:, 122:, 114:, 99:, 5712:· 5696:) 5692:( 5659:) 5548:) 5301:e 5294:t 5287:v 5270:. 5248:. 5222:. 5197:. 5145:. 5079:] 5076:P 5070:} 5064:, 5058:{ 5055:, 5043:L 5037:) 5034:l 5028:l 5025:( 4971:) 4962:X 4959:, 4956:P 4953:( 4941:, 4938:X 4935:( 4923:, 4920:K 4917:( 4908:X 4905:, 4902:K 4887:) 4875:, 4872:L 4869:( 4863:, 4860:L 4857:( 4838:) 4835:x 4832:( 4829:P 4820:, 4811:x 4808:, 4805:k 4787:l 4768:) 4765:x 4762:, 4759:k 4756:( 4750:) 4747:x 4744:( 4741:P 4735:X 4729:x 4723:K 4717:k 4705:l 4699:L 4693:l 4674:) 4671:x 4668:, 4665:k 4662:( 4653:x 4650:( 4647:P 4641:X 4635:x 4632:; 4629:K 4623:k 4620:( 4608:l 4602:) 4599:L 4593:l 4590:( 4549:x 4546:( 4543:P 4537:X 4531:x 4525:K 4519:k 4513:) 4510:x 4507:, 4504:k 4492:} 4489:L 4483:l 4477:l 4474:{ 4450:} 4447:) 4444:x 4441:( 4438:P 4432:X 4426:x 4420:K 4414:k 4407:| 4400:) 4397:x 4394:, 4391:k 4388:( 4385:{ 4364:} 4361:L 4355:l 4348:| 4341:l 4338:{ 4289:) 4285:( 4200:} 4197:) 4194:x 4191:( 4182:E 4176:x 4173:{ 4162:Y 4144:. 4141:] 4138:) 4135:x 4132:( 4123:E 4117:x 4111:Y 4105:x 4102:[ 4099:) 4096:x 4090:( 4087:) 4084:Y 4078:( 4075:) 4072:E 4066:( 4053:Φ 4048:E 4042:Y 4037:) 4035:x 4028:E 3997:} 3994:1 3991:, 3988:1 3982:{ 3962:1 3959:= 3955:| 3951:x 3947:| 3936:x 3922:1 3919:= 3914:2 3910:x 3899:x 3882:. 3879:) 3876:1 3873:= 3869:| 3865:x 3861:| 3853:Q 3846:x 3843:( 3837:) 3834:1 3831:= 3826:2 3822:x 3814:R 3807:x 3804:( 3778:} 3775:1 3772:= 3768:| 3764:x 3760:| 3752:Q 3745:x 3742:{ 3739:= 3736:} 3733:1 3730:= 3725:2 3721:x 3713:R 3706:x 3703:{ 3685:. 3673:] 3670:) 3667:) 3664:t 3661:( 3658:Q 3652:B 3646:t 3643:( 3637:) 3634:) 3631:t 3628:( 3625:P 3619:A 3613:t 3610:( 3607:[ 3604:) 3601:t 3595:( 3569:} 3566:) 3563:x 3560:( 3557:Q 3551:B 3545:x 3542:{ 3539:= 3536:} 3533:) 3530:x 3527:( 3524:P 3518:A 3512:x 3509:{ 3477:. 3474:} 3470:Z 3463:2 3459:/ 3455:) 3452:1 3446:u 3443:( 3437:u 3434:{ 3431:= 3428:} 3424:Z 3417:t 3411:1 3408:+ 3405:t 3402:2 3399:{ 3386:t 3372:2 3368:/ 3364:) 3361:1 3355:u 3352:( 3349:= 3346:t 3326:1 3323:+ 3320:t 3317:2 3314:= 3311:u 3291:} 3287:Z 3280:t 3274:1 3271:+ 3268:t 3265:2 3262:{ 3238:} 3234:Z 3227:t 3221:) 3218:1 3215:+ 3212:t 3209:2 3206:, 3203:t 3200:( 3197:{ 3175:} 3171:Z 3164:t 3158:1 3155:+ 3152:t 3149:2 3146:{ 3124:, 3120:Q 3098:Z 3077:} 3074:0 3068:q 3065:, 3061:Z 3054:q 3051:, 3048:p 3042:q 3038:/ 3034:p 3031:{ 3008:N 2987:} 2983:N 2976:n 2970:n 2967:2 2964:{ 2949:. 2937:} 2934:) 2931:) 2928:x 2925:( 2916:) 2913:x 2910:( 2907:f 2904:= 2901:y 2898:( 2895:x 2886:y 2883:{ 2880:= 2877:} 2874:) 2871:x 2868:( 2859:) 2856:x 2853:( 2850:f 2847:{ 2824:, 2821:} 2818:) 2815:x 2812:( 2803:) 2800:x 2797:( 2794:f 2791:{ 2771:} 2768:) 2765:x 2762:( 2753:x 2750:{ 2735:x 2723:. 2703:} 2700:] 2697:p 2694:= 2691:q 2688:a 2682:0 2676:q 2673:[ 2670:) 2666:Z 2659:q 2653:( 2650:) 2646:Z 2639:p 2633:( 2626:R 2619:a 2616:{ 2603:n 2588:} 2585:] 2582:k 2579:2 2576:= 2573:n 2570:[ 2567:) 2563:N 2556:k 2550:( 2544:n 2541:{ 2529:) 2527:x 2525:( 2523:P 2517:x 2502:) 2499:x 2496:( 2493:P 2490:) 2487:x 2481:( 2426:} 2423:] 2420:k 2417:2 2414:= 2411:n 2404:N 2397:k 2394:[ 2391:) 2388:k 2382:( 2375:N 2368:n 2365:{ 2342:R 2334:R 2319:f 2311:) 2309:x 2307:( 2305:f 2300:y 2286:} 2283:) 2280:x 2277:( 2274:f 2268:y 2262:0 2255:R 2247:R 2240:) 2237:y 2234:, 2231:x 2228:( 2225:{ 2215:. 2203:} 2197:, 2194:0 2191:, 2188:1 2182:, 2179:2 2173:{ 2170:= 2165:2 2158:G 2137:} 2131:, 2128:5 2125:, 2122:4 2119:, 2116:3 2113:{ 2110:= 2107:} 2104:3 2098:x 2091:Z 2084:x 2081:{ 2078:= 2073:3 2069:G 2048:} 2042:, 2039:2 2036:+ 2033:m 2030:, 2027:1 2024:+ 2021:m 2018:, 2015:m 2012:{ 2009:= 2006:} 2003:m 1997:x 1990:Z 1983:x 1980:{ 1977:= 1972:m 1968:G 1956:m 1934:} 1931:1 1928:= 1923:2 1919:x 1911:R 1904:x 1901:{ 1881:} 1878:1 1875:, 1872:1 1866:{ 1846:} 1843:1 1840:= 1836:| 1832:x 1828:| 1820:R 1813:x 1810:{ 1800:. 1788:) 1782:, 1779:0 1776:( 1745:} 1742:0 1736:x 1729:R 1722:x 1719:{ 1695:E 1677:, 1674:} 1671:x 1665:x 1658:| 1651:x 1648:{ 1589:} 1586:) 1583:x 1580:( 1575:2 1567:, 1564:) 1561:x 1558:( 1553:1 1542:E 1536:x 1533:{ 1513:} 1510:) 1507:x 1504:( 1495:E 1489:x 1486:{ 1466:) 1463:x 1460:( 1455:2 1444:) 1441:x 1438:( 1433:1 1408:) 1405:x 1402:( 1384:E 1378:x 1332:. 1329:} 1326:) 1323:x 1320:( 1311:E 1305:x 1299:x 1296:{ 1286:} 1283:) 1280:x 1277:( 1266:E 1260:x 1254:x 1251:{ 1225:, 1222:} 1219:) 1216:x 1213:( 1204:E 1198:x 1195:{ 1181:E 1167:x 1153:x 1138:} 1135:) 1132:x 1129:( 1120:x 1117:{ 1106:x 1100:x 1087:) 1085:x 1062:. 1059:} 1056:) 1053:x 1050:( 1044:: 1041:x 1038:{ 1012:} 1009:) 1006:x 1003:( 994:x 991:{ 935:} 915:{ 888:n 882:i 876:1 854:i 850:a 829:} 824:n 820:a 816:, 810:, 805:1 801:a 797:{ 754:} 751:0 748:, 742:, 739:1 736:{ 733:= 730:] 727:0 724:[ 704:0 701:= 698:n 678:] 675:n 672:[ 652:} 649:n 646:, 640:, 637:1 634:{ 614:n 608:i 602:1 582:i 562:} 559:n 556:, 550:, 547:1 544:{ 516:} 510:, 507:2 501:, 498:2 495:, 492:1 486:, 483:1 480:, 477:0 474:{ 471:= 468:} 462:, 459:2 456:, 453:1 450:, 447:0 444:, 441:1 435:, 432:2 426:, 420:{ 410:. 394:} 388:, 385:3 382:, 379:2 376:, 373:1 370:{ 348:} 342:, 336:, 333:3 330:, 327:2 324:, 321:1 318:{ 294:c 290:b 286:a 272:} 269:c 266:, 263:b 260:, 257:a 254:{ 251:= 248:} 245:b 242:, 239:c 236:, 233:a 230:{ 208:} 202:, 196:, 193:3 190:, 187:7 184:{ 79:} 76:k 73:2 70:= 67:n 64:, 60:Z 53:k 44:n 41:{ 20:)

Index

Set builder notation
even integers
set theory
logic
mathematics
computer science
mathematical notation
set
elements
intension
Set (mathematics) § Roster notation
set
ellipsis
natural numbers
empty set
predicate
colon
vertical bar
empty set
set membership
logical conjunction
Set existence axiom
domain of discourse
subset
Russell's paradox
positive
real numbers
interval notation
equivalent predicates yield equal sets
function

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