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Finitely generated group

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in the generators of the group represent the same element. The word problem for a given finitely generated group is solvable if and only if the group can be embedded in every
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all subgroups of the group are finitely generated. A group such that all its subgroups are finitely generated is called
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are the numbers of generators of the two finitely generated subgroups then their intersection is generated by at most
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on two generators is an example of a subgroup of a finitely generated group that is not finitely generated.
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of a generating set for the group. By definition, the rank of a finitely generated group is finite.
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of two finitely generated subgroups of a free group is again finitely generated. Furthermore, if
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On the other hand, all subgroups of a finitely generated abelian group are finitely generated.
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can be written as the combination (under the group operation) of finitely many elements of
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is finitely generated; the quotient group is generated by the images of the generators of
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studies the connections between algebraic properties of finitely generated groups and
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Howson, Albert G. (1954). "On the intersection of finitely generated free groups".
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Subgroups of a finitely generated abelian group are themselves finitely generated.
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A subgroup of a finitely generated group need not be finitely generated. The
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but countable groups need not be finitely generated. The additive group of
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A group such that every finitely generated subgroup is finite is called
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in a finitely generated group is always finitely generated, and the
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on a finite set is finitely generated by the elements of that set (
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is an example of a countable group that is not finitely generated.
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generators. This upper bound was then significantly improved by
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fundamental theorem of finitely generated abelian groups
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A group that is generated by a single element is called
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itself. Every infinite finitely generated group must be
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states that a finitely generated abelian group is the
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and a finite abelian group, each of which are unique
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gives a bound on the number of generators required.
180: 601:, every periodic abelian group is locally finite. 552: 492: 448: 428: 383: 807: 758: 850: 738:Proceedings of the American Mathematical Society 24:requires two generators, as represented by this 145:is a group in which every finitely generated 780:Journal of the London Mathematical Society 749: 731: 184: 15: 851: 776: 675:for a finitely generated group is the 734:"A note on finitely generated groups" 829: 813: 764: 694:is often defined to be the smallest 608: 13: 666: 14: 875: 751:10.1090/S0002-9939-1967-0215904-3 593:, i.e., every element has finite 181:Finitely generated abelian groups 127:. Every infinite cyclic group is 612: 589:. Every locally finite group is 228:finitely generated abelian group 206:Finitely generated abelian group 604: 770: 725: 541: 529: 526: 514: 108:of a finitely generated group 1: 823: 553:{\displaystyle 2(m-1)(n-1)+1} 131:to the additive group of the 76:is finitely generated, since 732:Gregorac, Robert J. (1967). 355: 7: 701: 98: 10: 880: 685:algebraically closed group 203: 708:Finitely generated module 573:ascending chain condition 571:of a group satisfies the 493:{\displaystyle 2mn-m-n+1} 57:so that every element of 22:dihedral group of order 8 832:A Course on Group Theory 793:10.1112/jlms/s1-29.4.428 718: 562:Hanna Neumann conjecture 176:) is finitely generated. 170:finitely presented group 38:finitely generated group 830:Rose, John S. (2012) . 713:Presentation of a group 834:. Dover Publications. 659:on which these groups 645:Geometric group theory 554: 494: 450: 430: 403:Schreier index formula 385: 246:, every group element 201: 29: 555: 495: 451: 431: 397:A subgroup of finite 386: 384:{\displaystyle F_{2}} 254:of these generators, 200:under multiplication. 188: 72:By definition, every 19: 864:Properties of groups 569:lattice of subgroups 508: 460: 440: 420: 368: 250:can be written as a 143:locally cyclic group 118:canonical projection 362:commutator subgroup 80:can be taken to be 69:of such elements. 624:. You can help by 550: 490: 446: 426: 381: 364:of the free group 342:free abelian group 252:linear combination 202: 30: 841:978-0-486-68194-8 642: 641: 449:{\displaystyle n} 429:{\displaystyle m} 214:can be seen as a 871: 845: 817: 811: 805: 804: 774: 768: 762: 756: 755: 753: 729: 677:decision problem 637: 634: 616: 609: 559: 557: 556: 551: 499: 497: 496: 491: 455: 453: 452: 447: 435: 433: 432: 427: 412:showed that the 410:Albert G. Howson 390: 388: 387: 382: 380: 379: 230:with generators 90:rational numbers 879: 878: 874: 873: 872: 870: 869: 868: 849: 848: 842: 826: 821: 820: 812: 808: 775: 771: 763: 759: 730: 726: 721: 704: 692:rank of a group 679:of whether two 669: 667:Related notions 638: 632: 629: 622:needs expansion 607: 509: 506: 505: 461: 458: 457: 441: 438: 437: 421: 418: 417: 375: 371: 369: 366: 365: 358: 325: 316: 306: 297: 288: 281: 274: 267: 245: 236: 208: 183: 101: 12: 11: 5: 877: 867: 866: 861: 847: 846: 840: 825: 822: 819: 818: 806: 787:(4): 428–434. 769: 757: 744:(4): 756–758. 723: 722: 720: 717: 716: 715: 710: 703: 700: 668: 665: 655:properties of 640: 639: 633:September 2017 619: 617: 606: 603: 587:locally finite 576:if and only if 549: 546: 543: 540: 537: 534: 531: 528: 525: 522: 519: 516: 513: 489: 486: 483: 480: 477: 474: 471: 468: 465: 445: 425: 378: 374: 357: 354: 321: 314: 310:with integers 308: 307: 302: 293: 286: 279: 272: 265: 241: 234: 204:Main article: 194:roots of unity 182: 179: 178: 177: 163: 152: 151: 150: 121: 100: 97: 52:generating set 47:that has some 9: 6: 4: 3: 2: 876: 865: 862: 860: 857: 856: 854: 843: 837: 833: 828: 827: 816:, p. 75. 815: 810: 802: 798: 794: 790: 786: 782: 781: 773: 767:, p. 55. 766: 761: 752: 747: 743: 739: 735: 728: 724: 714: 711: 709: 706: 705: 699: 697: 693: 688: 686: 682: 678: 674: 664: 662: 658: 654: 650: 646: 636: 627: 623: 620:This section 618: 615: 611: 610: 602: 600: 596: 592: 588: 583: 581: 577: 574: 570: 565: 563: 547: 544: 538: 535: 532: 523: 520: 517: 511: 503: 502:Hanna Neumann 487: 484: 481: 478: 475: 472: 469: 466: 463: 443: 423: 415: 411: 406: 404: 400: 395: 392: 376: 372: 363: 353: 352:isomorphism. 351: 347: 343: 339: 335: 330: 327: 324: 320: 313: 305: 301: 296: 292: 285: 278: 271: 264: 260: 257: 256: 255: 253: 249: 244: 240: 233: 229: 225: 221: 217: 213: 212:abelian group 207: 199: 195: 192: 187: 175: 171: 167: 164: 161: 157: 153: 148: 144: 140: 139: 137: 134: 130: 126: 122: 119: 115: 111: 107: 103: 102: 96: 94: 91: 87: 83: 79: 75: 70: 68: 64: 60: 56: 53: 50: 46: 43: 39: 35: 27: 26:cycle diagram 23: 18: 859:Group theory 831: 809: 784: 778: 772: 760: 741: 737: 727: 689: 673:word problem 670: 643: 630: 626:adding to it 621: 605:Applications 584: 566: 414:intersection 407: 396: 393: 359: 331: 328: 322: 318: 311: 309: 303: 299: 294: 290: 283: 276: 269: 262: 258: 247: 242: 238: 231: 223: 222:of integers 209: 198:cyclic group 189:The six 6th 135: 113: 109: 92: 81: 77: 74:finite group 71: 62: 58: 54: 44: 37: 31: 814:Rose (2012) 765:Rose (2012) 696:cardinality 649:topological 226:, and in a 853:Categories 824:References 599:Conversely 580:Noetherian 344:of finite 338:direct sum 166:A fortiori 156:free group 149:is cyclic. 129:isomorphic 116:under the 653:geometric 536:− 521:− 479:− 473:− 408:In 1954, 356:Subgroups 218:over the 174:§Examples 160:§Examples 86:countable 702:See also 591:periodic 289:+ ... + 168:, every 147:subgroup 133:integers 106:quotient 99:Examples 67:inverses 801:0065557 317:, ..., 237:, ..., 196:form a 191:complex 65:and of 34:algebra 838:  799:  657:spaces 560:; see 216:module 210:Every 125:cyclic 104:Every 49:finite 719:Notes 681:words 595:order 399:index 350:up to 340:of a 42:group 40:is a 836:ISBN 690:The 671:The 651:and 567:The 436:and 346:rank 332:The 220:ring 154:The 36:, a 20:The 789:doi 746:doi 661:act 628:. 504:to 32:In 855:: 797:MR 795:. 785:29 783:. 742:18 740:. 736:. 687:. 663:. 597:. 582:. 564:. 326:. 275:+ 261:= 162:). 141:A 138:. 844:. 803:. 791:: 754:. 748:: 635:) 631:( 548:1 545:+ 542:) 539:1 533:n 530:( 527:) 524:1 518:m 515:( 512:2 488:1 485:+ 482:n 476:m 470:n 467:m 464:2 444:n 424:m 377:2 373:F 323:n 319:α 315:1 312:α 304:n 300:x 298:â‹… 295:n 291:α 287:2 284:x 282:â‹… 280:2 277:α 273:1 270:x 268:â‹… 266:1 263:α 259:x 248:x 243:n 239:x 235:1 232:x 224:Z 172:( 136:Z 120:. 114:G 110:G 93:Q 82:G 78:S 63:S 59:G 55:S 45:G 28:.

Index


dihedral group of order 8
cycle diagram
algebra
group
finite
generating set
inverses
finite group
countable
rational numbers
quotient
canonical projection
cyclic
isomorphic
integers
locally cyclic group
subgroup
free group
§Examples
A fortiori
finitely presented group
§Examples

complex
roots of unity
cyclic group
Finitely generated abelian group
abelian group
module

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