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1642: 1629: 1063: 1053: 1023: 1013: 991: 981: 946: 924: 914: 879: 847: 837: 812: 780: 765: 745: 713: 703: 693: 673: 641: 621: 611: 601: 569: 549: 505: 485: 475: 438: 413: 403: 371: 346: 309: 279: 247: 185: 150: 4404:. Specifically, a complete join-semilattice requires that the homomorphisms preserve all joins, but contrary to the situation we find for completeness properties, this does not require that homomorphisms preserve all meets. On the other hand, we can conclude that every such mapping is the lower adjoint of some 4388:
Nowadays, the term "complete semilattice" has no generally accepted meaning, and various mutually inconsistent definitions exist. If completeness is taken to require the existence of all infinite joins, or all infinite meets, whichever the case may be, as well as finite ones, this immediately leads
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Surprisingly, there is a notion of "distributivity" applicable to semilattices, even though distributivity conventionally requires the interaction of two binary operations. This notion requires but a single operation, and generalizes the distributivity condition for lattices. A join-semilattice is
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joins. If such a structure has also a greatest element (the meet of the empty set), it is also a complete lattice. Thus a complete semilattice turns out to be "a complete lattice possibly lacking a top". This definition is of interest specifically in
1888:, and any such operation induces a partial order (and the respective inverse order) such that the result of the operation for any two elements is the least upper bound (or greatest lower bound) of the elements with respect to this partial order. 1373: 1302: 3842: 1895:
is a partially ordered set that is both a meet- and join-semilattice with respect to the same partial order. Algebraically, a lattice is a set with two associative, commutative idempotent binary operations linked by corresponding
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By induction on the number of elements, any non-empty finite meet semilattice has a least element and any non-empty finite join semilattice has a greatest element. (In neither case will the semilattice necessarily be
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Distributive meet-semilattices are defined dually. These definitions are justified by the fact that any distributive join-semilattice in which binary meets exist is a distributive lattice. See the entry
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indicates that the property is not guaranteed in general (it might, or might not, hold). For example, that every equivalence relation is symmetric, but not necessarily antisymmetric, is indicated by
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Hence the two definitions may be used interchangeably, depending on which one is more convenient for a particular purpose. A similar conclusion holds for join-semilattices and the dual ordering ≥.
4712:). The case of free meet-semilattices is dual, using the opposite subset inclusion as an ordering. For join-semilattices with bottom, we just add the empty set to the above collection of subsets. 3260: 1572: 1469: 1425: 1384: 1313: 1242: 1186: 4694: 4400:
Nevertheless, the literature on occasion still takes complete join- or meet-semilattices to be complete lattices. In this case, "completeness" denotes a restriction on the scope of the
2661: 2500: 4239: 4167: 4422:. A complete meet-semilattice in this sense is arguably the "most complete" meet-semilattice that is not necessarily a complete lattice. Indeed, a complete meet-semilattice has all 3687: 1175: 1561: 4287: 4263: 4108: 3751: 3630: 3574: 3216: 3040: 3002: 3286: 4023: 3783: 3719: 3606: 1308: 1715: 1237: 3386: 2417:
argument shows that the existence of all possible pairwise suprema (infima), as per the definition, implies the existence of all non-empty finite suprema (infima).
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In addition, semilattices often serve as generators for free objects within other categories. Notably, both the forgetful functors from the category of
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It is often the case that standard treatments of lattice theory define a semilattice, if that, and then say no more. See the references in the entries
2965:, hence in particular a meet-semilattice and join-semilattice: any two distinct elements have a greater and lesser one, which are their meet and join. 1567: 1181: 3291: 3936: 2447:
for more discussion on this subject. That article also discusses how we may rephrase the above definition in terms of the existence of suitable
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are a bounded join-semilattice, with least element 0, although they have no greatest element: they are the smallest infinite well-ordered set.
1464: 4408:. The corresponding (unique) upper adjoint will then be a homomorphism of complete meet-semilattices. This gives rise to a number of useful 4393:. For why the existence of all possible infinite joins entails the existence of all possible infinite meets (and vice versa), see the entry 1420: 1379: 50: 3046:. It has a least element (the empty word), which is an annihilator element of the meet operation, but no greatest (identity) element. 3537: 3518: 4172: 3042:
is a (generally unbounded) meet-semilattice. Consider for example the set of finite words over some alphabet, ordered by the
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In the order-theoretic formulation, these conditions just state that a homomorphism of join-semilattices is a function that
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defines a join-semilattice, with join read as binary fusion. This semilattice is bounded from above by the world individual.
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and frame-homomorphisms, and from the category of distributive lattices and lattice-homomorphisms, have a left adjoint.
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Semilattices are employed to construct other order structures, or in conjunction with other completeness properties.
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and 0 with 1—transforms this definition of a join-semilattice homomorphism into its meet-semilattice equivalent.
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between the categories of all complete semilattices with morphisms preserving all meets or joins, respectively.
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Cardinality-restricted notions of completeness for semilattices have been rarely considered in the literature.
43: 2634: 2473: 4874: 4370: 4212: 4113: 2217: 3663: 4394: 2444: 2086: 1151: 4814: 4788: 1535: 4409: 3549: 2718:. One can be ambivalent about the particular choice of symbol for the operation, and speak simply of 36: 4268: 4244: 4081: 3724: 3611: 3555: 3195: 4854: 4806: 4716: 1110: 934: 103: 3022: 2985: 1368:{\displaystyle {\begin{aligned}a\neq {}&b\Rightarrow \\aRb{\text{ or }}&bRa\end{aligned}}} 4869: 2177: 3265: 4419: 3996: 3756: 3692: 3579: 2547: 2429: 2414: 1843: 1297:{\displaystyle {\begin{aligned}aRb{\text{ and }}&bRa\\\Rightarrow a={}&b\end{aligned}}} 1080: 73: 3837:{\displaystyle \operatorname {Id} \ f\colon \operatorname {Id} \ S\to \operatorname {Id} \ T} 2258: 1821: 1635:
indicates that the column's property is always true the row's term (at the very left), while
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is both a join- and a meet-semilattice. The interaction of these two semilattices via the
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may be recovered. Conversely, the order induced by the algebraically defined semilattice
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A term's definition may require additional properties that are not listed in this table.
1746: 1720: 1679: 1508: 1125: 1115: 526: 108: 25: 4061: 3976: 3887: 3867: 3847: 3643: 2737: 2377: 2327: 1988: 1979: 1937: 1855: 1825: 1661: 1105: 1085: 1075: 1001: 98: 78: 68: 4840:. Moreover, there is no literature on semilattices of comparable magnitude to that on 1862:) for any nonempty finite subset. Every join-semilattice is a meet-semilattice in the 4818: 4792: 4467: 4405: 3633: 3533: 3362:. This semilattice is bounded, with the least element being the singleton partition 3016: 2980: 2503: 2448: 2250: 1829: 4731: – Mathematical ordering with upper bounds − generalization of join semilattice 4778: 4709: 4475: 4416: 4390: 3536:
with respect to the associated ordering relation. For an explanation see the entry
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join-semilattice, as the set as a whole has a least element, hence it is bounded.
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introduced in this way defines a partial ordering from which the binary operation
2033: 4471: 4459: 4436: 4055: 3637: 2947: 2943: 2932: 2842: 2452: 2262: 2100: 2094: 2081: 2061: 2052: 2018: 1955: 1892: 661: 458: 29: 4837: 3074: 2936: 2142: 1897: 1612:{\displaystyle {\begin{aligned}aRb\Rightarrow \\{\text{not }}bRa\end{aligned}}} 329: 1226:{\displaystyle {\begin{aligned}&aRb\\\Rightarrow {}&bRa\end{aligned}}} 4863: 4432: 3640:-preserving complete join-homomorphisms, as follows. With a join-semilattice 2726: 2586: 2554: 2425: 2028: 1993: 1950: 1878: 1874: 1863: 1100: 1095: 267: 93: 88: 4702:
suffices to obtain the required adjunction—the morphism-part of the functor
3355:{\displaystyle \xi \vee \eta =\{P\cap Q\mid P\in \xi \ \&\ Q\in \eta \}} 4833: 4728: 4440: 4427: 4401: 3418: 3063: 3050: 3043: 2795:. In a bounded meet-semilattice, the identity 1 is the greatest element of 2202: 2133: 1967: 1833: 3966:{\displaystyle \operatorname {Id} \colon {\mathcal {S}}\to {\mathcal {A}}} 4463: 3126: 2802:
Similarly, an identity element in a join semilattice is a least element.
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from the category of join-semilattices (and their homomorphisms) to the
1497:{\displaystyle {\begin{aligned}a\wedge b\\{\text{exists}}\end{aligned}}} 3479: 1942: 1836: 589: 2950:, under the induced partial ordering, form a bounded join-semilattice. 1453:{\displaystyle {\begin{aligned}a\vee b\\{\text{exists}}\end{aligned}}} 4841: 4376:
A join-semilattice is distributive if and only if the lattice of its
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The above algebraic definition of a semilattice suggests a notion of
3153: 2733: 2197: 2003: 1960: 1928: 1409:{\displaystyle {\begin{aligned}\min S\\{\text{exists}}\end{aligned}}} 4742: – Algebraic ring that need not have additive negative elements 4739: 4078:, and with every compactness-preserving complete join-homomorphism 3398: 2833:
is an algebraic meet-semilattice. Conversely, the meet-semilattice
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and least elements, if such there be. The obvious dual—replacing
2295: 1870: 4763:, Graduate Texts in Mathematics Volume 26, Springer 1976, p. 57 4499: 3501: 2741: 1932: 1839: 4426:
meets (which is equivalent to being bounded complete) and all
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is a join-semilattice. In fact, the partial order is given by
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are in fact the same set. Commutativity and associativity of
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between related posets — an approach of special interest for
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A partial order is induced on a meet-semilattice by setting
2771:. For a join-semilattice, the order is induced by setting 4495:
is constructed by taking the collection of all non-empty
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Another usage of "complete meet-semilattice" refers to a
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is what truly distinguishes a lattice from a semilattice.
2805: 4202:{\displaystyle K\colon {\mathcal {A}}\to {\mathcal {S}}} 4110:
between algebraic lattices we associate the restriction
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in the definition just given, the structure is called a
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Note that any semilattice homomorphism is necessarily
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between two semilattices. Given two join-semilattices
3019:(with the single root as the least element) of height 4271: 4247: 4215: 4175: 4116: 4084: 4064: 4031: 3999: 3979: 3939: 3910: 3890: 3870: 3850: 3791: 3759: 3727: 3695: 3666: 3646: 3614: 3582: 3558: 3368: 3294: 3268: 3224: 3198: 3172: 3025: 2988: 2740:. A bounded semilattice is an idempotent commutative 2637: 2476: 1775: 1749: 1723: 1688: 1664: 1570: 1538: 1511: 1467: 1423: 1382: 1311: 1240: 1184: 1154: 1128: 3255:{\displaystyle \forall Q\in \eta ,\exists P\in \xi } 2443:
Other properties may be assumed; see the article on
4688: 4281: 4257: 4233: 4201: 4161: 4102: 4070: 4046: 4017: 3985: 3965: 3925: 3896: 3876: 3856: 3836: 3777: 3745: 3713: 3681: 3652: 3624: 3600: 3568: 3380: 3354: 3280: 3254: 3210: 3178: 3073:because a semilattice captures the essence of set 3034: 2996: 2655: 2494: 1790: 1761: 1735: 1709: 1670: 1611: 1555: 1523: 1496: 1452: 1408: 1367: 1296: 1225: 1169: 1140: 4861: 4708:can be derived from general considerations (see 3504:homomorphism, i.e. we additionally require that 1387: 4776: 3108:Two sets differing only in one or both of the: 2244: 2225: 1652:in the "Antisymmetric" column, respectively. 44: 4680: 4651: 4292: 3375: 3369: 3349: 3307: 2650: 2638: 2489: 2477: 4689:{\textstyle f'(A)=\bigvee \{f(s)|s\in A\}.} 4458:This section presupposes some knowledge of 3973:. Conversely, with every algebraic lattice 3288:and the join of two partitions is given by 3660:with zero, we associate its ideal lattice 2232: 2218: 51: 37: 4570:(more formally, to the underlying set of 2990: 1854:) is a partially ordered set which has a 4383: 3392: 3147:because a set is not a member of itself. 3113:Order in which their members are listed; 2656:{\displaystyle \langle S,\land \rangle } 2495:{\displaystyle \langle S,\land \rangle } 4805: 4478:. Therefore, the free join-semilattice 4443:. Hence Scott domains have been called 4241:defines a category equivalence between 4234:{\displaystyle (\operatorname {Id} ,K)} 4162:{\displaystyle K(f)\colon K(A)\to K(B)} 2854:in the following way: for all elements 2458: 2356:Replacing "greatest lower bound" with " 4862: 4509:ordered by subset inclusion. Clearly, 3682:{\displaystyle \operatorname {Id} \ S} 3421:of (join-) semilattices is a function 2806:Connection between the two definitions 4466:semilattices exist. For example, the 3494:both include a least element 0, then 3482:associated with each semilattice. If 4453: 3785:-semilattices, we associate the map 3576:of join-semilattices with zero with 3116:Multiplicity of one or more members, 2810:An order theoretic meet-semilattice 2314:The greatest lower bound of the set 1655:All definitions tacitly require the 4389:to partial orders that are in fact 4380:(under inclusion) is distributive. 3544:Equivalence with algebraic lattices 2360:" results in the dual concept of a 1170:{\displaystyle S\neq \varnothing :} 13: 4853:Jipsen's algebra structures page: 4784:Introduction to Lattices and Order 4274: 4250: 4194: 4184: 3958: 3948: 3617: 3561: 3478:is just a homomorphism of the two 3334: 3240: 3225: 14: 4886: 4847: 4474:of sets (and functions) admits a 1869:Semilattices can also be defined 1161: 4576:) induces a unique homomorphism 3608:-homomorphisms and the category 1640: 1627: 1556:{\displaystyle {\text{not }}aRa} 1061: 1051: 1021: 1011: 989: 979: 944: 922: 912: 877: 845: 835: 810: 778: 763: 743: 711: 701: 691: 671: 639: 619: 609: 599: 567: 547: 503: 483: 473: 436: 411: 401: 369: 344: 307: 277: 245: 183: 148: 3129:, (2). This semilattice is the 3066:of a semilattice with base set 2913:coincides with that induced by 2455:investigations of the concept. 4753: 4696:Now the obvious uniqueness of 4667: 4663: 4657: 4642: 4636: 4582:between the join-semilattices 4282:{\displaystyle {\mathcal {A}}} 4258:{\displaystyle {\mathcal {S}}} 4228: 4216: 4189: 4156: 4150: 4144: 4141: 4135: 4126: 4120: 4103:{\displaystyle f\colon A\to B} 4094: 4041: 4035: 4012: 4000: 3953: 3920: 3914: 3819: 3772: 3760: 3746:{\displaystyle f\colon S\to T} 3737: 3708: 3696: 3625:{\displaystyle {\mathcal {A}}} 3595: 3583: 3569:{\displaystyle {\mathcal {S}}} 3211:{\displaystyle \xi \leq \eta } 1648:in the "Symmetric" column and 1584: 1329: 1274: 1203: 1: 4770: 4371:distributivity (order theory) 3166:the collection of partitions 2440:, the meet of the empty set. 2428:, the join of the empty set. 1649: 1636: 1046: 1041: 1036: 1031: 1006: 974: 969: 964: 959: 954: 939: 907: 902: 897: 892: 887: 872: 860: 855: 830: 825: 820: 805: 793: 788: 773: 758: 753: 738: 726: 721: 686: 681: 666: 654: 649: 634: 629: 594: 582: 577: 562: 557: 542: 537: 532: 518: 513: 498: 493: 468: 463: 451: 446: 431: 426: 421: 396: 384: 379: 364: 359: 354: 339: 334: 322: 317: 302: 297: 292: 287: 272: 260: 255: 240: 235: 230: 225: 220: 215: 198: 193: 178: 173: 168: 163: 158: 3035:{\displaystyle \leq \omega } 2997:{\displaystyle \mathbb {N} } 2522:, such that for all members 2445:completeness in order theory 7: 4722: 4395:completeness (order theory) 2922: 2364:. The least upper bound of 10: 4891: 4815:Cambridge University Press 4789:Cambridge University Press 3281:{\displaystyle Q\subset P} 2245:Order-theoretic definition 4462:. In various situations, 4435:, where bounded complete 4293:Distributive semilattices 4169:. This defines a functor 4018:{\displaystyle (\vee ,0)} 3933:. This defines a functor 3778:{\displaystyle (\vee ,0)} 3714:{\displaystyle (\vee ,0)} 3601:{\displaystyle (\vee ,0)} 3004:, with their usual order 4746: 3884:associates the ideal of 2432:, a meet-semilattice is 16:Partial order with joins 4532:that takes any element 4690: 4564:to a join-semilattice 4445:algebraic semilattices 4283: 4259: 4235: 4203: 4163: 4104: 4072: 4048: 4019: 3987: 3967: 3927: 3898: 3878: 3858: 3844:, that with any ideal 3838: 3779: 3747: 3715: 3683: 3654: 3626: 3602: 3570: 3548:There is a well-known 3538:preservation of limits 3519:preserves binary joins 3382: 3356: 3282: 3256: 3212: 3180: 3152:Classical extensional 3056:Membership in any set 3053:is a meet-semilattice. 3036: 2998: 2848:that partially orders 2736:; i.e., a commutative 2657: 2496: 2420:A join-semilattice is 1792: 1763: 1737: 1711: 1710:{\displaystyle a,b,c,} 1672: 1613: 1557: 1525: 1498: 1454: 1410: 1369: 1298: 1227: 1171: 1142: 4691: 4544:to the singleton set 4515:can be embedded into 4410:categorical dualities 4384:Complete semilattices 4284: 4260: 4236: 4204: 4164: 4105: 4073: 4049: 4020: 3988: 3968: 3928: 3899: 3879: 3859: 3839: 3780: 3748: 3716: 3684: 3655: 3627: 3603: 3571: 3552:between the category 3393:Semilattice morphisms 3383: 3381:{\displaystyle \{S\}} 3357: 3283: 3257: 3213: 3181: 3140:It is not bounded by 3037: 2999: 2658: 2497: 1822:partially ordered set 1793: 1764: 1738: 1712: 1673: 1614: 1558: 1526: 1499: 1455: 1411: 1370: 1299: 1228: 1172: 1143: 1122:Definitions, for all 4875:Algebraic structures 4735:List of order topics 4625: 4439:cpos are studied as 4269: 4245: 4213: 4173: 4114: 4082: 4062: 4047:{\displaystyle K(A)} 4029: 3997: 3977: 3937: 3926:{\displaystyle f(I)} 3908: 3888: 3868: 3848: 3789: 3757: 3725: 3693: 3664: 3644: 3612: 3580: 3556: 3366: 3292: 3266: 3222: 3196: 3179:{\displaystyle \xi } 3170: 3023: 2986: 2963:distributive lattice 2635: 2474: 2459:Algebraic definition 2402:. Meet and join are 2296:greatest lower bound 2129:Group with operators 2072:Complemented lattice 1907:Algebraic structures 1873:: join and meet are 1860:greatest lower bound 1791:{\displaystyle aRc.} 1773: 1747: 1721: 1686: 1662: 1657:homogeneous relation 1568: 1536: 1509: 1465: 1421: 1380: 1309: 1238: 1182: 1152: 1126: 868:Strict partial order 143:Equivalence relation 4787:(second ed.). 3062:can be taken as a 2959:totally ordered set 2725:A semilattice is a 2631:A meet-semilattice 2469:algebraic structure 2183:Composition algebra 1943:Quasigroup and loop 1762:{\displaystyle bRc} 1736:{\displaystyle aRb} 1524:{\displaystyle aRa} 1141:{\displaystyle a,b} 527:Well-quasi-ordering 4811:Topology via Logic 4761:Algebraic theories 4686: 4552:Then any function 4279: 4255: 4231: 4199: 4159: 4100: 4068: 4044: 4015: 3983: 3963: 3923: 3894: 3874: 3854: 3834: 3775: 3743: 3711: 3679: 3650: 3634:algebraic lattices 3622: 3598: 3566: 3378: 3352: 3278: 3252: 3208: 3176: 3032: 3015:Any single-rooted 2994: 2653: 2492: 2453:category theoretic 2449:Galois connections 1788: 1759: 1733: 1707: 1668: 1609: 1607: 1553: 1521: 1494: 1492: 1450: 1448: 1406: 1404: 1365: 1363: 1294: 1292: 1223: 1221: 1167: 1138: 1002:Strict total order 4468:forgetful functor 4454:Free semilattices 4406:Galois connection 4391:complete lattices 4071:{\displaystyle A} 3993:we associate the 3986:{\displaystyle A} 3897:{\displaystyle T} 3877:{\displaystyle S} 3857:{\displaystyle I} 3830: 3815: 3800: 3675: 3653:{\displaystyle S} 3500:should also be a 3339: 3333: 2404:binary operations 2358:least upper bound 2276:For all elements 2259:partially ordered 2242: 2241: 1886:binary operations 1852:lower semilattice 1830:least upper bound 1818:upper semilattice 1804: 1803: 1671:{\displaystyle R} 1622: 1621: 1594: 1542: 1488: 1444: 1400: 1348: 1257: 935:Strict weak order 121:Total, Semiconnex 4882: 4828: 4802: 4779:Priestley, H. A. 4764: 4757: 4710:adjoint functors 4707: 4701: 4695: 4693: 4692: 4687: 4670: 4635: 4620: 4614: 4599: 4592: 4581: 4575: 4569: 4563: 4557: 4551: 4543: 4537: 4531: 4525: 4514: 4508: 4494: 4488: 4417:bounded complete 4367: 4352: 4342: 4332: 4318: 4312: 4288: 4286: 4285: 4280: 4278: 4277: 4264: 4262: 4261: 4256: 4254: 4253: 4240: 4238: 4237: 4232: 4208: 4206: 4205: 4200: 4198: 4197: 4188: 4187: 4168: 4166: 4165: 4160: 4109: 4107: 4106: 4101: 4077: 4075: 4074: 4069: 4056:compact elements 4053: 4051: 4050: 4045: 4024: 4022: 4021: 4016: 3992: 3990: 3989: 3984: 3972: 3970: 3969: 3964: 3962: 3961: 3952: 3951: 3932: 3930: 3929: 3924: 3903: 3901: 3900: 3895: 3883: 3881: 3880: 3875: 3863: 3861: 3860: 3855: 3843: 3841: 3840: 3835: 3828: 3813: 3798: 3784: 3782: 3781: 3776: 3752: 3750: 3749: 3744: 3720: 3718: 3717: 3712: 3688: 3686: 3685: 3680: 3673: 3659: 3657: 3656: 3651: 3631: 3629: 3628: 3623: 3621: 3620: 3607: 3605: 3604: 3599: 3575: 3573: 3572: 3567: 3565: 3564: 3528: 3524: 3513: 3499: 3493: 3487: 3477: 3468: 3434: 3416: 3408: 3387: 3385: 3384: 3379: 3361: 3359: 3358: 3353: 3337: 3331: 3287: 3285: 3284: 3279: 3261: 3259: 3258: 3253: 3217: 3215: 3214: 3209: 3191: 3185: 3183: 3182: 3177: 3165: 3146: 3139: 3131:free semilattice 3124: 3107: 3096: 3086: 3072: 3061: 3041: 3039: 3038: 3033: 3007: 3003: 3001: 3000: 2995: 2993: 2970:well-ordered set 2946:of an algebraic 2944:compact elements 2916: 2912: 2904: 2900: 2894: 2879: 2865: 2859: 2853: 2847: 2841:gives rise to a 2840: 2832: 2824: 2820:binary operation 2818:gives rise to a 2817: 2801: 2794: 2780: 2770: 2756: 2716:join-semilattice 2713: 2705: 2699: 2692: 2686: 2675:identity element 2672: 2662: 2660: 2659: 2654: 2627: 2607: 2583: 2545: 2538: 2532: 2517: 2513:binary operation 2510: 2502:consisting of a 2501: 2499: 2498: 2493: 2465:meet-semilattice 2438:greatest element 2412: 2401: 2391: 2385: 2375: 2362:join-semilattice 2353: 2342: 2335: 2325: 2309: 2293: 2287: 2281: 2270:meet-semilattice 2267: 2257: 2234: 2227: 2220: 2009:Commutative ring 1938:Rack and quandle 1903: 1902: 1866:and vice versa. 1848:meet-semilattice 1814:join-semilattice 1797: 1795: 1794: 1789: 1768: 1766: 1765: 1760: 1742: 1740: 1739: 1734: 1716: 1714: 1713: 1708: 1677: 1675: 1674: 1669: 1651: 1647: 1644: 1643: 1638: 1634: 1631: 1630: 1618: 1616: 1615: 1610: 1608: 1595: 1592: 1562: 1560: 1559: 1554: 1543: 1540: 1530: 1528: 1527: 1522: 1503: 1501: 1500: 1495: 1493: 1489: 1486: 1459: 1457: 1456: 1451: 1449: 1445: 1442: 1415: 1413: 1412: 1407: 1405: 1401: 1398: 1374: 1372: 1371: 1366: 1364: 1349: 1346: 1323: 1303: 1301: 1300: 1295: 1293: 1284: 1258: 1255: 1232: 1230: 1229: 1224: 1222: 1207: 1188: 1176: 1174: 1173: 1168: 1147: 1145: 1144: 1139: 1068: 1065: 1064: 1058: 1055: 1054: 1048: 1043: 1038: 1033: 1028: 1025: 1024: 1018: 1015: 1014: 1008: 996: 993: 992: 986: 983: 982: 976: 971: 966: 961: 956: 951: 948: 947: 941: 929: 926: 925: 919: 916: 915: 909: 904: 899: 894: 889: 884: 881: 880: 874: 862: 857: 852: 849: 848: 842: 839: 838: 832: 827: 822: 817: 814: 813: 807: 801:Meet-semilattice 795: 790: 785: 782: 781: 775: 770: 767: 766: 760: 755: 750: 747: 746: 740: 734:Join-semilattice 728: 723: 718: 715: 714: 708: 705: 704: 698: 695: 694: 688: 683: 678: 675: 674: 668: 656: 651: 646: 643: 642: 636: 631: 626: 623: 622: 616: 613: 612: 606: 603: 602: 596: 584: 579: 574: 571: 570: 564: 559: 554: 551: 550: 544: 539: 534: 529: 520: 515: 510: 507: 506: 500: 495: 490: 487: 486: 480: 477: 476: 470: 465: 453: 448: 443: 440: 439: 433: 428: 423: 418: 415: 414: 408: 405: 404: 398: 386: 381: 376: 373: 372: 366: 361: 356: 351: 348: 347: 341: 336: 324: 319: 314: 311: 310: 304: 299: 294: 289: 284: 281: 280: 274: 262: 257: 252: 249: 248: 242: 237: 232: 227: 222: 217: 212: 210: 200: 195: 190: 187: 186: 180: 175: 170: 165: 160: 155: 152: 151: 145: 63: 62: 53: 46: 39: 32: 30:binary relations 21: 20: 4890: 4889: 4885: 4884: 4883: 4881: 4880: 4879: 4860: 4859: 4850: 4825: 4807:Vickers, Steven 4799: 4773: 4768: 4767: 4758: 4754: 4749: 4725: 4703: 4697: 4666: 4628: 4626: 4623: 4622: 4616: 4601: 4594: 4583: 4577: 4571: 4565: 4559: 4553: 4545: 4539: 4533: 4527: 4516: 4510: 4503: 4490: 4479: 4460:category theory 4456: 4386: 4354: 4344: 4334: 4320: 4314: 4303: 4295: 4273: 4272: 4270: 4267: 4266: 4249: 4248: 4246: 4243: 4242: 4214: 4211: 4210: 4193: 4192: 4183: 4182: 4174: 4171: 4170: 4115: 4112: 4111: 4083: 4080: 4079: 4063: 4060: 4059: 4030: 4027: 4026: 3998: 3995: 3994: 3978: 3975: 3974: 3957: 3956: 3947: 3946: 3938: 3935: 3934: 3909: 3906: 3905: 3889: 3886: 3885: 3869: 3866: 3865: 3849: 3846: 3845: 3790: 3787: 3786: 3758: 3755: 3754: 3726: 3723: 3722: 3694: 3691: 3690: 3665: 3662: 3661: 3645: 3642: 3641: 3616: 3615: 3613: 3610: 3609: 3581: 3578: 3577: 3560: 3559: 3557: 3554: 3553: 3546: 3526: 3522: 3508: 3495: 3489: 3483: 3473: 3439: 3422: 3410: 3402: 3395: 3367: 3364: 3363: 3293: 3290: 3289: 3267: 3264: 3263: 3223: 3220: 3219: 3197: 3194: 3193: 3187: 3171: 3168: 3167: 3160: 3141: 3134: 3122: 3098: 3088: 3078: 3067: 3057: 3024: 3021: 3020: 3005: 2989: 2987: 2984: 2983: 2981:natural numbers 2925: 2914: 2906: 2902: 2898: 2881: 2880:if and only if 2867: 2861: 2855: 2849: 2845: 2843:binary relation 2834: 2826: 2822: 2811: 2808: 2796: 2782: 2772: 2758: 2748: 2711: 2703: 2694: 2688: 2678: 2668: 2636: 2633: 2632: 2615: 2591: 2559: 2540: 2534: 2523: 2515: 2506: 2475: 2472: 2471: 2461: 2407: 2393: 2387: 2381: 2365: 2344: 2337: 2331: 2315: 2299: 2289: 2283: 2277: 2265: 2263:binary relation 2253: 2247: 2238: 2209: 2208: 2207: 2178:Non-associative 2160: 2149: 2148: 2138: 2118: 2107: 2106: 2095:Map of lattices 2091: 2087:Boolean algebra 2082:Heyting algebra 2056: 2045: 2044: 2038: 2019:Integral domain 1983: 1972: 1971: 1965: 1919: 1898:absorption laws 1806: 1805: 1798: 1774: 1771: 1770: 1748: 1745: 1744: 1722: 1719: 1718: 1687: 1684: 1683: 1663: 1660: 1659: 1653: 1645: 1641: 1632: 1628: 1606: 1605: 1591: 1588: 1587: 1571: 1569: 1566: 1565: 1539: 1537: 1534: 1533: 1510: 1507: 1506: 1491: 1490: 1485: 1482: 1481: 1468: 1466: 1463: 1462: 1447: 1446: 1441: 1438: 1437: 1424: 1422: 1419: 1418: 1403: 1402: 1397: 1394: 1393: 1383: 1381: 1378: 1377: 1362: 1361: 1350: 1345: 1333: 1332: 1324: 1322: 1312: 1310: 1307: 1306: 1291: 1290: 1285: 1283: 1271: 1270: 1259: 1256: and  1254: 1241: 1239: 1236: 1235: 1220: 1219: 1208: 1206: 1200: 1199: 1185: 1183: 1180: 1179: 1153: 1150: 1149: 1127: 1124: 1123: 1066: 1062: 1056: 1052: 1026: 1022: 1016: 1012: 994: 990: 984: 980: 949: 945: 927: 923: 917: 913: 882: 878: 850: 846: 840: 836: 815: 811: 783: 779: 768: 764: 748: 744: 716: 712: 706: 702: 696: 692: 676: 672: 644: 640: 624: 620: 614: 610: 604: 600: 572: 568: 552: 548: 525: 508: 504: 488: 484: 478: 474: 459:Prewellordering 441: 437: 416: 412: 406: 402: 374: 370: 349: 345: 312: 308: 282: 278: 250: 246: 208: 205: 188: 184: 153: 149: 141: 133: 57: 24: 17: 12: 11: 5: 4888: 4878: 4877: 4872: 4870:Lattice theory 4858: 4857: 4849: 4848:External links 4846: 4838:lattice theory 4830: 4829: 4823: 4803: 4797: 4777:Davey, B. A.; 4772: 4769: 4766: 4765: 4751: 4750: 4748: 4745: 4744: 4743: 4737: 4732: 4724: 4721: 4685: 4682: 4679: 4676: 4673: 4669: 4665: 4662: 4659: 4656: 4653: 4650: 4647: 4644: 4641: 4638: 4634: 4631: 4455: 4452: 4385: 4382: 4294: 4291: 4276: 4252: 4230: 4227: 4224: 4221: 4218: 4196: 4191: 4186: 4181: 4178: 4158: 4155: 4152: 4149: 4146: 4143: 4140: 4137: 4134: 4131: 4128: 4125: 4122: 4119: 4099: 4096: 4093: 4090: 4087: 4067: 4043: 4040: 4037: 4034: 4014: 4011: 4008: 4005: 4002: 3982: 3960: 3955: 3950: 3945: 3942: 3922: 3919: 3916: 3913: 3893: 3873: 3853: 3833: 3827: 3824: 3821: 3818: 3812: 3809: 3806: 3803: 3797: 3794: 3774: 3771: 3768: 3765: 3762: 3742: 3739: 3736: 3733: 3730: 3721:-homomorphism 3710: 3707: 3704: 3701: 3698: 3678: 3672: 3669: 3649: 3619: 3597: 3594: 3591: 3588: 3585: 3563: 3545: 3542: 3515: 3514: 3470: 3469: 3394: 3391: 3390: 3389: 3377: 3374: 3371: 3351: 3348: 3345: 3342: 3336: 3330: 3327: 3324: 3321: 3318: 3315: 3312: 3309: 3306: 3303: 3300: 3297: 3277: 3274: 3271: 3251: 3248: 3245: 3242: 3239: 3236: 3233: 3230: 3227: 3207: 3204: 3201: 3175: 3157: 3149: 3148: 3118: 3117: 3114: 3110: 3109: 3075:extensionality 3054: 3047: 3031: 3028: 3013: 3012: 3011: 3010: 3009: 2992: 2955: 2951: 2940: 2937:absorption law 2924: 2921: 2807: 2804: 2702:If the symbol 2652: 2649: 2646: 2643: 2640: 2629: 2628: 2613: 2608: 2589: 2584: 2557: 2546:the following 2491: 2488: 2485: 2482: 2479: 2460: 2457: 2376:is called the 2326:is called the 2312: 2311: 2246: 2243: 2240: 2239: 2237: 2236: 2229: 2222: 2214: 2211: 2210: 2206: 2205: 2200: 2195: 2190: 2185: 2180: 2175: 2169: 2168: 2167: 2161: 2155: 2154: 2151: 2150: 2147: 2146: 2143:Linear algebra 2137: 2136: 2131: 2126: 2120: 2119: 2113: 2112: 2109: 2108: 2105: 2104: 2101:Lattice theory 2097: 2090: 2089: 2084: 2079: 2074: 2069: 2064: 2058: 2057: 2051: 2050: 2047: 2046: 2037: 2036: 2031: 2026: 2021: 2016: 2011: 2006: 2001: 1996: 1991: 1985: 1984: 1978: 1977: 1974: 1973: 1964: 1963: 1958: 1953: 1947: 1946: 1945: 1940: 1935: 1926: 1920: 1914: 1913: 1910: 1909: 1802: 1801: 1787: 1784: 1781: 1778: 1758: 1755: 1752: 1732: 1729: 1726: 1706: 1703: 1700: 1697: 1694: 1691: 1667: 1624: 1623: 1620: 1619: 1604: 1601: 1598: 1590: 1589: 1586: 1583: 1580: 1577: 1574: 1573: 1563: 1552: 1549: 1546: 1531: 1520: 1517: 1514: 1504: 1484: 1483: 1480: 1477: 1474: 1471: 1470: 1460: 1440: 1439: 1436: 1433: 1430: 1427: 1426: 1416: 1396: 1395: 1392: 1389: 1386: 1385: 1375: 1360: 1357: 1354: 1351: 1347: or  1344: 1341: 1338: 1335: 1334: 1331: 1328: 1325: 1321: 1318: 1315: 1314: 1304: 1289: 1286: 1282: 1279: 1276: 1273: 1272: 1269: 1266: 1263: 1260: 1253: 1250: 1247: 1244: 1243: 1233: 1218: 1215: 1212: 1209: 1205: 1202: 1201: 1198: 1195: 1192: 1189: 1187: 1177: 1166: 1163: 1160: 1157: 1137: 1134: 1131: 1119: 1118: 1113: 1108: 1103: 1098: 1093: 1088: 1083: 1078: 1073: 1070: 1069: 1059: 1049: 1044: 1039: 1034: 1029: 1019: 1009: 1004: 998: 997: 987: 977: 972: 967: 962: 957: 952: 942: 937: 931: 930: 920: 910: 905: 900: 895: 890: 885: 875: 870: 864: 863: 858: 853: 843: 833: 828: 823: 818: 808: 803: 797: 796: 791: 786: 776: 771: 761: 756: 751: 741: 736: 730: 729: 724: 719: 709: 699: 689: 684: 679: 669: 664: 658: 657: 652: 647: 637: 632: 627: 617: 607: 597: 592: 586: 585: 580: 575: 565: 560: 555: 545: 540: 535: 530: 522: 521: 516: 511: 501: 496: 491: 481: 471: 466: 461: 455: 454: 449: 444: 434: 429: 424: 419: 409: 399: 394: 388: 387: 382: 377: 367: 362: 357: 352: 342: 337: 332: 330:Total preorder 326: 325: 320: 315: 305: 300: 295: 290: 285: 275: 270: 264: 263: 258: 253: 243: 238: 233: 228: 223: 218: 213: 202: 201: 196: 191: 181: 176: 171: 166: 161: 156: 146: 138: 137: 135: 130: 128: 126: 124: 122: 119: 117: 115: 112: 111: 106: 101: 96: 91: 86: 81: 76: 71: 66: 59: 58: 56: 55: 48: 41: 33: 19: 18: 15: 9: 6: 4: 3: 2: 4887: 4876: 4873: 4871: 4868: 4867: 4865: 4856: 4855:Semilattices. 4852: 4851: 4845: 4843: 4839: 4835: 4826: 4824:0-521-36062-5 4820: 4816: 4812: 4808: 4804: 4800: 4798:0-521-78451-4 4794: 4790: 4786: 4785: 4780: 4775: 4774: 4762: 4759:E. G. Manes, 4756: 4752: 4741: 4738: 4736: 4733: 4730: 4727: 4726: 4720: 4718: 4713: 4711: 4706: 4700: 4683: 4677: 4674: 4671: 4660: 4654: 4648: 4645: 4639: 4632: 4629: 4619: 4612: 4608: 4604: 4597: 4590: 4586: 4580: 4574: 4568: 4562: 4556: 4549: 4542: 4536: 4530: 4526:by a mapping 4523: 4519: 4513: 4506: 4501: 4498: 4493: 4486: 4482: 4477: 4473: 4469: 4465: 4461: 4451: 4448: 4446: 4442: 4441:Scott domains 4438: 4434: 4433:domain theory 4429: 4425: 4421: 4418: 4413: 4411: 4407: 4403: 4402:homomorphisms 4398: 4396: 4392: 4381: 4379: 4374: 4372: 4365: 4361: 4357: 4351: 4347: 4341: 4337: 4331: 4327: 4323: 4317: 4310: 4306: 4301: 4290: 4225: 4222: 4219: 4179: 4176: 4153: 4147: 4138: 4132: 4129: 4123: 4117: 4097: 4091: 4088: 4085: 4065: 4057: 4038: 4032: 4025:-semilattice 4009: 4006: 4003: 3980: 3943: 3940: 3917: 3911: 3904:generated by 3891: 3871: 3851: 3831: 3825: 3822: 3816: 3810: 3807: 3804: 3801: 3795: 3792: 3769: 3766: 3763: 3740: 3734: 3731: 3728: 3705: 3702: 3699: 3676: 3670: 3667: 3647: 3639: 3635: 3592: 3589: 3586: 3551: 3541: 3539: 3535: 3530: 3520: 3511: 3507: 3506: 3505: 3503: 3498: 3492: 3486: 3481: 3476: 3466: 3462: 3458: 3454: 3450: 3446: 3442: 3438: 3437: 3436: 3433: 3429: 3425: 3420: 3414: 3406: 3400: 3372: 3346: 3343: 3340: 3328: 3325: 3322: 3319: 3316: 3313: 3310: 3304: 3301: 3298: 3295: 3275: 3272: 3269: 3249: 3246: 3243: 3237: 3234: 3231: 3228: 3205: 3202: 3199: 3190: 3173: 3163: 3158: 3155: 3151: 3150: 3144: 3137: 3132: 3128: 3120: 3119: 3115: 3112: 3111: 3105: 3101: 3095: 3091: 3085: 3081: 3076: 3070: 3065: 3060: 3055: 3052: 3048: 3045: 3029: 3026: 3018: 3014: 2982: 2978: 2977: 2975: 2972:is further a 2971: 2967: 2966: 2964: 2960: 2956: 2952: 2949: 2945: 2941: 2938: 2934: 2930: 2929: 2928: 2920: 2917: 2910: 2897:The relation 2895: 2892: 2888: 2884: 2878: 2874: 2870: 2864: 2858: 2852: 2844: 2838: 2830: 2821: 2815: 2803: 2799: 2793: 2789: 2785: 2779: 2775: 2769: 2765: 2761: 2755: 2751: 2745: 2743: 2739: 2735: 2732: 2728: 2723: 2721: 2717: 2709: 2700: 2697: 2691: 2685: 2681: 2676: 2671: 2666: 2647: 2644: 2641: 2626: 2622: 2618: 2614: 2612: 2609: 2606: 2602: 2598: 2594: 2590: 2588: 2587:Commutativity 2585: 2582: 2578: 2574: 2570: 2566: 2562: 2558: 2556: 2555:Associativity 2553: 2552: 2551: 2549: 2543: 2537: 2530: 2526: 2521: 2514: 2509: 2505: 2486: 2483: 2480: 2470: 2466: 2456: 2454: 2450: 2446: 2441: 2439: 2435: 2431: 2427: 2426:least element 2423: 2418: 2416: 2410: 2405: 2400: 2396: 2390: 2384: 2379: 2373: 2369: 2363: 2359: 2354: 2351: 2347: 2340: 2334: 2329: 2323: 2319: 2307: 2303: 2297: 2292: 2286: 2280: 2275: 2274: 2273: 2271: 2264: 2260: 2256: 2252: 2235: 2230: 2228: 2223: 2221: 2216: 2215: 2213: 2212: 2204: 2201: 2199: 2196: 2194: 2191: 2189: 2186: 2184: 2181: 2179: 2176: 2174: 2171: 2170: 2166: 2163: 2162: 2158: 2153: 2152: 2145: 2144: 2140: 2139: 2135: 2132: 2130: 2127: 2125: 2122: 2121: 2116: 2111: 2110: 2103: 2102: 2098: 2096: 2093: 2092: 2088: 2085: 2083: 2080: 2078: 2075: 2073: 2070: 2068: 2065: 2063: 2060: 2059: 2054: 2049: 2048: 2043: 2042: 2035: 2032: 2030: 2029:Division ring 2027: 2025: 2022: 2020: 2017: 2015: 2012: 2010: 2007: 2005: 2002: 2000: 1997: 1995: 1992: 1990: 1987: 1986: 1981: 1976: 1975: 1970: 1969: 1962: 1959: 1957: 1954: 1952: 1951:Abelian group 1949: 1948: 1944: 1941: 1939: 1936: 1934: 1930: 1927: 1925: 1922: 1921: 1917: 1912: 1911: 1908: 1905: 1904: 1901: 1899: 1894: 1889: 1887: 1884: 1880: 1876: 1872: 1871:algebraically 1867: 1865: 1864:inverse order 1861: 1857: 1853: 1849: 1845: 1841: 1838: 1835: 1831: 1827: 1823: 1819: 1815: 1811: 1800: 1785: 1782: 1779: 1776: 1756: 1753: 1750: 1730: 1727: 1724: 1704: 1701: 1698: 1695: 1692: 1689: 1681: 1665: 1658: 1626: 1625: 1602: 1599: 1596: 1581: 1578: 1575: 1564: 1550: 1547: 1544: 1532: 1518: 1515: 1512: 1505: 1478: 1475: 1472: 1461: 1434: 1431: 1428: 1417: 1390: 1376: 1358: 1355: 1352: 1342: 1339: 1336: 1326: 1319: 1316: 1305: 1287: 1280: 1277: 1267: 1264: 1261: 1251: 1248: 1245: 1234: 1216: 1213: 1210: 1196: 1193: 1190: 1178: 1164: 1158: 1155: 1135: 1132: 1129: 1121: 1120: 1117: 1114: 1112: 1109: 1107: 1104: 1102: 1099: 1097: 1094: 1092: 1089: 1087: 1084: 1082: 1081:Antisymmetric 1079: 1077: 1074: 1072: 1071: 1060: 1050: 1045: 1040: 1035: 1030: 1020: 1010: 1005: 1003: 1000: 999: 988: 978: 973: 968: 963: 958: 953: 943: 938: 936: 933: 932: 921: 911: 906: 901: 896: 891: 886: 876: 871: 869: 866: 865: 859: 854: 844: 834: 829: 824: 819: 809: 804: 802: 799: 798: 792: 787: 777: 772: 762: 757: 752: 742: 737: 735: 732: 731: 725: 720: 710: 700: 690: 685: 680: 670: 665: 663: 660: 659: 653: 648: 638: 633: 628: 618: 608: 598: 593: 591: 590:Well-ordering 588: 587: 581: 576: 566: 561: 556: 546: 541: 536: 531: 528: 524: 523: 517: 512: 502: 497: 492: 482: 472: 467: 462: 460: 457: 456: 450: 445: 435: 430: 425: 420: 410: 400: 395: 393: 390: 389: 383: 378: 368: 363: 358: 353: 343: 338: 333: 331: 328: 327: 321: 316: 306: 301: 296: 291: 286: 276: 271: 269: 268:Partial order 266: 265: 259: 254: 244: 239: 234: 229: 224: 219: 214: 211: 204: 203: 197: 192: 182: 177: 172: 167: 162: 157: 147: 144: 140: 139: 136: 131: 129: 127: 125: 123: 120: 118: 116: 114: 113: 110: 107: 105: 102: 100: 97: 95: 92: 90: 87: 85: 82: 80: 77: 75: 74:Antisymmetric 72: 70: 67: 65: 64: 61: 60: 54: 49: 47: 42: 40: 35: 34: 31: 27: 23: 22: 4834:order theory 4831: 4810: 4783: 4760: 4755: 4729:Directed set 4714: 4704: 4698: 4621:is given by 4617: 4615:Explicitly, 4610: 4606: 4602: 4595: 4588: 4584: 4578: 4572: 4566: 4560: 4554: 4547: 4540: 4534: 4528: 4521: 4517: 4511: 4504: 4496: 4491: 4484: 4480: 4476:left adjoint 4457: 4449: 4444: 4423: 4414: 4399: 4387: 4375: 4363: 4359: 4355: 4349: 4345: 4339: 4335: 4333:there exist 4329: 4325: 4321: 4315: 4308: 4304: 4300:distributive 4299: 4296: 3547: 3531: 3516: 3509: 3496: 3490: 3484: 3474: 3471: 3464: 3460: 3456: 3452: 3448: 3444: 3440: 3431: 3427: 3423: 3419:homomorphism 3412: 3404: 3396: 3188: 3161: 3159:Given a set 3142: 3135: 3125:assure (1), 3103: 3099: 3093: 3089: 3083: 3079: 3068: 3058: 3051:Scott domain 3044:prefix order 2973: 2926: 2918: 2908: 2896: 2890: 2886: 2882: 2876: 2872: 2868: 2862: 2856: 2850: 2836: 2828: 2813: 2809: 2797: 2791: 2787: 2783: 2777: 2773: 2767: 2763: 2759: 2753: 2749: 2746: 2724: 2720:semilattices 2719: 2715: 2707: 2701: 2695: 2689: 2683: 2679: 2677:1 such that 2673:includes an 2669: 2664: 2630: 2624: 2620: 2616: 2604: 2600: 2596: 2592: 2580: 2576: 2572: 2568: 2564: 2560: 2541: 2535: 2528: 2524: 2519: 2507: 2464: 2462: 2442: 2436:if it has a 2433: 2424:if it has a 2421: 2419: 2408: 2398: 2394: 2388: 2382: 2371: 2367: 2361: 2355: 2349: 2345: 2338: 2332: 2321: 2317: 2313: 2305: 2301: 2290: 2284: 2278: 2269: 2254: 2248: 2203:Hopf algebra 2141: 2134:Vector space 2099: 2066: 2039: 1968:Group theory 1966: 1931: / 1890: 1868: 1851: 1847: 1817: 1813: 1807: 1654: 1091:Well-founded 209:(Quasiorder) 84:Well-founded 4489:over a set 4302:if for all 4209:. The pair 3638:compactness 3550:equivalence 3127:idempotence 2911:, ∧⟩ 2839:, ∧⟩ 2831:, ∧⟩ 2816:, ≤⟩ 2727:commutative 2710:, replaces 2611:Idempotency 2298:of the set 2188:Lie algebra 2173:Associative 2077:Total order 2067:Semilattice 2041:Ring theory 1879:commutative 1875:associative 1824:that has a 1810:mathematics 1111:Irreflexive 392:Total order 104:Irreflexive 4864:Categories 4842:semigroups 4771:References 4600:such that 4353:such that 3480:semigroups 3435:such that 3262:such that 2825:such that 2731:idempotent 2548:identities 2392:, denoted 1883:idempotent 1832:) for any 1682:: for all 1680:transitive 1116:Asymmetric 109:Asymmetric 26:Transitive 4675:∈ 4649:⋁ 4437:algebraic 4424:non-empty 4190:→ 4180:: 4145:→ 4130:: 4095:→ 4089:: 4004:∨ 3954:→ 3944:: 3826:⁡ 3820:→ 3811:⁡ 3805:: 3796:⁡ 3764:∨ 3738:→ 3732:: 3700:∨ 3689:. With a 3671:⁡ 3587:∨ 3347:η 3344:∈ 3335:& 3329:ξ 3326:∈ 3320:∣ 3314:∩ 3302:η 3299:∨ 3296:ξ 3273:⊂ 3250:ξ 3247:∈ 3241:∃ 3235:η 3232:∈ 3226:∀ 3206:η 3203:≤ 3200:ξ 3174:ξ 3154:mereology 3030:ω 3027:≤ 2954:bounded.) 2781:whenever 2757:whenever 2734:semigroup 2706:, called 2651:⟩ 2648:∧ 2639:⟨ 2518:, called 2490:⟩ 2487:∧ 2478:⟨ 2415:induction 2413:A simple 2198:Bialgebra 2004:Near-ring 1961:Lie group 1929:Semigroup 1593:not  1585:⇒ 1541:not  1476:∧ 1432:∨ 1330:⇒ 1320:≠ 1275:⇒ 1204:⇒ 1162:∅ 1159:≠ 1106:Reflexive 1101:Has meets 1096:Has joins 1086:Connected 1076:Symmetric 207:Preorder 134:reflexive 99:Reflexive 94:Has meets 89:Has joins 79:Connected 69:Symmetric 4809:(1989). 4781:(2002). 4740:Semiring 4723:See also 4633:′ 4472:category 4428:directed 4362:∨ 4348:≤ 4338:≤ 4328:∨ 4324:≤ 3534:monotone 3512:(0) = 0. 3399:morphism 2923:Examples 2907:⟨ 2835:⟨ 2827:⟨ 2812:⟨ 2687:for all 2343:denoted 2034:Lie ring 1999:Semiring 1834:nonempty 1650:✗ 1637:✗ 1047:✗ 1042:✗ 1037:✗ 1032:✗ 1007:✗ 975:✗ 970:✗ 965:✗ 960:✗ 955:✗ 940:✗ 908:✗ 903:✗ 898:✗ 893:✗ 888:✗ 873:✗ 861:✗ 856:✗ 831:✗ 826:✗ 821:✗ 806:✗ 794:✗ 789:✗ 774:✗ 759:✗ 754:✗ 739:✗ 727:✗ 722:✗ 687:✗ 682:✗ 667:✗ 655:✗ 650:✗ 635:✗ 630:✗ 595:✗ 583:✗ 578:✗ 563:✗ 558:✗ 543:✗ 538:✗ 533:✗ 519:✗ 514:✗ 499:✗ 494:✗ 469:✗ 464:✗ 452:✗ 447:✗ 432:✗ 427:✗ 422:✗ 397:✗ 385:✗ 380:✗ 365:✗ 360:✗ 355:✗ 340:✗ 335:✗ 323:✗ 318:✗ 303:✗ 298:✗ 293:✗ 288:✗ 273:✗ 261:✗ 256:✗ 241:✗ 236:✗ 231:✗ 226:✗ 221:✗ 216:✗ 199:✗ 194:✗ 179:✗ 174:✗ 169:✗ 164:✗ 159:✗ 4558:from a 4500:subsets 4054:of all 3087:denote 2974:bounded 2948:lattice 2933:lattice 2665:bounded 2511:with a 2434:bounded 2422:bounded 2310:exists. 2261:by the 2165:Algebra 2157:Algebra 2062:Lattice 2053:Lattice 1893:lattice 1820:) is a 662:Lattice 4821:  4795:  4717:frames 4497:finite 4378:ideals 3829:  3814:  3799:  3674:  3502:monoid 3472:Hence 3338:  3332:  3097:& 3077:. Let 2742:monoid 2682:∧ 1 = 2550:hold: 2467:is an 2430:Dually 2294:, the 2193:Graded 2124:Module 2115:Module 2014:Domain 1933:Monoid 1844:Dually 1840:subset 1837:finite 1487:exists 1443:exists 1399:exists 28:  4747:Notes 4319:with 3636:with 3525:with 3133:over 3064:model 2961:is a 2571:) = ( 2268:is a 2159:-like 2117:-like 2055:-like 2024:Field 1982:-like 1956:Magma 1924:Group 1918:-like 1916:Group 1769:then 132:Anti- 4836:and 4819:ISBN 4793:ISBN 4593:and 4464:free 4343:and 4313:and 4265:and 3488:and 3459:) ∨ 3451:) = 3417:, a 3415:, ∨) 3409:and 3407:, ∨) 3017:tree 2979:The 2942:The 2860:and 2738:band 2708:join 2579:) ∧ 2533:and 2520:meet 2386:and 2378:join 2336:and 2328:meet 2282:and 1989:Ring 1980:Ring 1858:(or 1856:meet 1850:(or 1846:, a 1826:join 1816:(or 1812:, a 1743:and 1148:and 4699:f' 4618:f' 4607:f' 4579:f' 4538:in 4502:of 4420:cpo 4364:b' 4360:a' 4346:b' 4336:a' 4058:of 3864:of 3753:of 3632:of 3218:if 3186:of 2866:in 2693:in 2667:if 2663:is 2563:∧ ( 2539:of 2504:set 2406:on 2380:of 2330:of 2288:of 2272:if 2251:set 1994:Rng 1828:(a 1808:In 1717:if 1678:be 1388:min 4866:: 4844:. 4817:. 4813:. 4791:. 4609:○ 4605:= 4550:}. 4447:. 4397:. 4373:. 4358:= 4307:, 4289:. 4220:Id 3941:Id 3823:Id 3808:Id 3793:Id 3668:Id 3540:. 3467:). 3447:∨ 3430:→ 3426:: 3102:∈ 3092:∈ 3082:∧ 3049:A 3006:≤, 2968:A 2957:A 2931:A 2915:≤. 2889:∧ 2885:= 2875:≤ 2871:, 2790:= 2786:∨ 2776:≤ 2766:= 2762:∧ 2752:≤ 2744:. 2729:, 2722:. 2623:= 2619:∧ 2603:∧ 2599:= 2595:∧ 2575:∧ 2567:∧ 2527:, 2463:A 2397:∨ 2370:, 2348:∧ 2320:, 2304:, 2249:A 1900:. 1891:A 1881:, 1877:, 1842:. 4827:. 4801:. 4705:F 4684:. 4681:} 4678:A 4672:s 4668:| 4664:) 4661:s 4658:( 4655:f 4652:{ 4646:= 4643:) 4640:A 4637:( 4630:f 4613:. 4611:e 4603:f 4598:, 4596:T 4591:) 4589:S 4587:( 4585:F 4573:T 4567:T 4561:S 4555:f 4548:s 4546:{ 4541:S 4535:s 4529:e 4524:) 4522:S 4520:( 4518:F 4512:S 4507:, 4505:S 4492:S 4487:) 4485:S 4483:( 4481:F 4366:. 4356:x 4350:b 4340:a 4330:b 4326:a 4322:x 4316:x 4311:, 4309:b 4305:a 4275:A 4251:S 4229:) 4226:K 4223:, 4217:( 4195:S 4185:A 4177:K 4157:) 4154:B 4151:( 4148:K 4142:) 4139:A 4136:( 4133:K 4127:) 4124:f 4121:( 4118:K 4098:B 4092:A 4086:f 4066:A 4042:) 4039:A 4036:( 4033:K 4013:) 4010:0 4007:, 4001:( 3981:A 3959:A 3949:S 3921:) 3918:I 3915:( 3912:f 3892:T 3872:S 3852:I 3832:T 3817:S 3802:f 3773:) 3770:0 3767:, 3761:( 3741:T 3735:S 3729:f 3709:) 3706:0 3703:, 3697:( 3677:S 3648:S 3618:A 3596:) 3593:0 3590:, 3584:( 3562:S 3527:∨ 3523:∧ 3510:f 3497:f 3491:T 3485:S 3475:f 3465:y 3463:( 3461:f 3457:x 3455:( 3453:f 3449:y 3445:x 3443:( 3441:f 3432:T 3428:S 3424:f 3413:T 3411:( 3405:S 3403:( 3388:. 3376:} 3373:S 3370:{ 3350:} 3341:Q 3323:P 3317:Q 3311:P 3308:{ 3305:= 3276:P 3270:Q 3244:P 3238:, 3229:Q 3189:S 3164:, 3162:S 3145:, 3143:L 3138:. 3136:L 3123:∧ 3106:. 3104:L 3100:b 3094:L 3090:a 3084:b 3080:a 3071:, 3069:L 3059:L 2991:N 2909:S 2903:∧ 2899:≤ 2893:. 2891:y 2887:x 2883:x 2877:y 2873:x 2869:S 2863:y 2857:x 2851:S 2846:≤ 2837:S 2829:S 2823:∧ 2814:S 2800:. 2798:S 2792:y 2788:y 2784:x 2778:y 2774:x 2768:x 2764:y 2760:x 2754:y 2750:x 2712:∧ 2704:∨ 2698:. 2696:S 2690:x 2684:x 2680:x 2670:S 2645:, 2642:S 2625:x 2621:x 2617:x 2605:x 2601:y 2597:y 2593:x 2581:z 2577:y 2573:x 2569:z 2565:y 2561:x 2544:, 2542:S 2536:z 2531:, 2529:y 2525:x 2516:∧ 2508:S 2484:, 2481:S 2411:. 2409:S 2399:y 2395:x 2389:y 2383:x 2374:} 2372:y 2368:x 2366:{ 2352:. 2350:y 2346:x 2341:, 2339:y 2333:x 2324:} 2322:y 2318:x 2316:{ 2308:} 2306:y 2302:x 2300:{ 2291:S 2285:y 2279:x 2266:≤ 2255:S 2233:e 2226:t 2219:v 1786:. 1783:c 1780:R 1777:a 1757:c 1754:R 1751:b 1731:b 1728:R 1725:a 1705:, 1702:c 1699:, 1696:b 1693:, 1690:a 1666:R 1646:Y 1633:Y 1603:a 1600:R 1597:b 1582:b 1579:R 1576:a 1551:a 1548:R 1545:a 1519:a 1516:R 1513:a 1479:b 1473:a 1435:b 1429:a 1391:S 1359:a 1356:R 1353:b 1343:b 1340:R 1337:a 1327:b 1317:a 1288:b 1281:= 1278:a 1268:a 1265:R 1262:b 1252:b 1249:R 1246:a 1217:a 1214:R 1211:b 1197:b 1194:R 1191:a 1165:: 1156:S 1136:b 1133:, 1130:a 1067:Y 1057:Y 1027:Y 1017:Y 995:Y 985:Y 950:Y 928:Y 918:Y 883:Y 851:Y 841:Y 816:Y 784:Y 769:Y 749:Y 717:Y 707:Y 697:Y 677:Y 645:Y 625:Y 615:Y 605:Y 573:Y 553:Y 509:Y 489:Y 479:Y 442:Y 417:Y 407:Y 375:Y 350:Y 313:Y 283:Y 251:Y 189:Y 154:Y 52:e 45:t 38:v

Index

Transitive
binary relations
v
t
e
Symmetric
Antisymmetric
Connected
Well-founded
Has joins
Has meets
Reflexive
Irreflexive
Asymmetric
Equivalence relation
Preorder (Quasiorder)
Partial order
Total preorder
Total order
Prewellordering
Well-quasi-ordering
Well-ordering
Lattice
Join-semilattice
Meet-semilattice
Strict partial order
Strict weak order
Strict total order
Symmetric
Antisymmetric

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