Knowledge

Flexagon

Source đź“ť

340:
gray, and yellow. Note the different patterns used for the colors on the two sides. Figure 3 shows the first fold, and figure 4 the result of the first nine folds, which form a spiral. Figures 5-6 show the final folding of the spiral to make a hexagon; in 5, two red faces have been hidden by a valley fold, and in 6, two red faces on the bottom side have been hidden by a mountain fold. After figure 6, the final loose triangle is folded over and attached to the other end of the original strip so that one side is all blue, and the other all orange. Photos 7 and 8 show the process of everting the hexaflexagon to show the formerly hidden red triangles. By further manipulations, all six colors can be exposed.
336: 33: 329: 205: 360:
triangles with different colors, and they can be seen by flexing the hexahexaflexagon in all possible ways in theory, but only 15 can be flexed by the ordinary hexahexaflexagon. The 3 extra configurations are impossible due to the arrangement of the 4, 5, and 6 tiles at the back flap. (The 60-degree angles in the rhombi formed by the adjacent 4, 5, or 6 tiles will only appear on the sides and never will appear at the center because it would require one to cut the strip, which is topologically forbidden.)
265: 197: 248: 293: 339:
Figures 1-6 show the construction of a hexaflexagon made out of cardboard triangles on a backing made from a strip of cloth. It has been decorated in six colours; orange, blue, and red in figure 1 correspond to 1, 2, and 3 in the diagram above. The opposite side, figure 2, is decorated with purple,
372:
While the most commonly seen hexaflexagons have either three or six faces, variations exist with any number of faces. Straight strips produce hexaflexagons with a multiple of three number of faces. Other numbers are obtained from nonstraight strips, that are just straight strips with some joints
347:
An easy way to expose all six faces is using the Tuckerman traverse, named after Bryant Tuckerman, one of the first to investigate the properties of hexaflexagons. The Tuckerman traverse involves the repeated flexing by pinching one corner and flex from exactly the same corner every time. If the
359:
Each color/face can also be exposed in more than one way. In figure 6, for example, each blue triangle has at the center its corner decorated with a wedge, but it is also possible, for example, to make the ones decorated with Y's come to the center. There are 18 such possible configurations for
386:
In these more recently discovered flexagons, each square or equilateral triangular face of a conventional flexagon is further divided into two right triangles, permitting additional flexing modes. The division of the square faces of tetraflexagons into right isosceles triangles yields the
260:
A more complicated cyclic hexatetraflexagon requires no gluing. A cyclic hexatetraflexagon does not have any "dead ends", but the person making it can keep folding it until they reach the starting position. If the sides are colored in the process, the states can be seen more clearly.
407:, with angles 72–54–54. Because of its fivefold symmetry, the pentaflexagon cannot be folded in half. However, a complex series of flexes results in its transformation from displaying sides one and two on the front and back, to displaying its previously hidden sides three and four. 296:
This trihexaflexagon template shows 3 colors of 9 triangles, printed on one side, and folded to be colored on both sides. The two yellow triangles on the ends will end up taped together. The red and blue arcs are seen as full circles on the inside of one side or the other when
363:
Hexahexaflexagons can be constructed from different shaped nets of eighteen equilateral triangles. One hexahexaflexagon, constructed from an irregular paper strip, is almost identical to the one shown above, except that all 18 configurations can be flexed on this version.
301:
A hexaflexagon with three faces is the simplest of the hexaflexagons to make and to manage, and is made from a single strip of paper, divided into nine equilateral triangles. (Some patterns provide ten triangles, two of which are glued together in the final assembly.)
127:
method, called the Tuckerman traverse, for revealing all the faces of a flexagon. Tuckerman traverses are shown as a diagram that maps each face of the flexagon to each other face. In doing so, he realized that each face does not always appear in the same state.
348:
corner refuses to open, move to an adjacent corner and keep flexing. This procedure brings you to a 12-face cycle. During this procedure, however, 1, 2, and 3 show up three times as frequently as 4, 5, and 6. The cycle proceeds as follows:
71:). A prefix can be added to the name to indicate the number of faces that the model can display, including the two faces (back and front) that are visible before flexing. For example, a hexaflexagon with a total of six faces is called a 110:
in the United States in 1939. His new American paper would not fit in his English binder so he cut off the ends of the paper and began folding them into different shapes. One of these formed a trihexaflexagon. Stone's colleagues
228:
sides). The "tri" in the name means it has three faces, two of which are visible at any given time if the flexagon is pressed flat. The construction of the tritetraflexagon is similar to the mechanism used in the traditional
170:
Their patent imagined possible applications of the device "as a toy, as an advertising display device, or as an educational geometric device." A few such novelties were produced by the
167:
applied for a patent, and in 1959 they were granted U.S. Patent number 2,883,195 for the hexahexaflexagon, under the title "Changeable Amusement Devices and the Like."
1380: 244:
The tritetraflexagon has two dead ends, where you cannot flex forward. To get to another face you must either flex backwards or flip the flexagon over.
280:
Hexaflexagons come in great variety, distinguished by the number of faces that can be achieved by flexing the assembled figure. (Note that the word
410:
By further dividing the 72-54-54 triangles of the pentaflexagon into 36-54-90 right triangles produces one variation of the 10-sided decaflexagon.
373:
folded, eliminating some faces. Many strips can be folded in different ways, producing different hexaflexagons, with different folding maps.
305:
To assemble, the strip is folded every third triangle, connecting back to itself after three inversions in the manner of the international
704: 1373: 387:
octaflexagons, and the division of the triangular faces of the hexaflexagons into 30-60-90 right triangles yields the dodecaflexagons.
85:
Two flexagons are equivalent if one can be transformed to the other by a series of pinches and rotations. Flexagon equivalence is an
1366: 1269: 1161: 1044: 453:. These should be distinguished from the "ordinary" pentaflexagons and heptaflexagons described above, which are made out of 1615: 1154:
Hexaflexagons, Probability Paradoxes, and the Tower of Hanoi: Martin Gardner's First Book of Mathematical Puzzles and Games
426:
isosceles triangles. Other flexagons include the heptaflexagon, the isosceles octaflexagon, the enneaflexagon, and others.
734: 1636: 272:
Contrary to the tritetraflexagon, the hexatetraflexagon has no dead ends, and does not ever need to be flexed backwards.
1536: 171: 1250: 1231: 1143: 1125: 1071: 687: 1322: 1788: 1173: 78:
In hexaflexagon theory (that is, concerning flexagons with six sides), flexagons are usually defined in terms of
17: 1747: 1677: 1474: 1443: 437:
also describes "nonplanar" flexagons (i.e., ones which cannot be flexed so they lie flat); ones folded from
1622: 1389: 1118:
Hexaflexagons and Other Mathematical Diversions: The First "Scientific American" Book of Puzzles and Games
1778: 680:
Hexaflexagons and Other Mathematical Diversions: The First Scientific American Book of Puzzles and Games
1672: 1001: 56:
or folded in certain ways to reveal faces besides the two that were originally on the back and front.
142: 1341: 971: 1707: 1643: 1413: 474: 325:
This hexaflexagon has six faces. It is made up of nineteen triangles folded from a strip of paper.
123:
became interested in the idea and formed the Princeton Flexagon Committee. Tuckerman worked out a
1549: 1285: 230: 164: 149:
included a construct-your-own hexaflexagon with the original cast recording of his Broadway show
102:
The discovery of the first flexagon, a trihexaflexagon, is credited to the British mathematician
1036: 1783: 1433: 1194: 538: 284:
can sometimes refer to an ordinary hexahexaflexagon, with six sides instead of other numbers.)
1418: 1061: 1593: 1423: 1403: 107: 86: 418:
The pentaflexagon is one of an infinite sequence of flexagons based on dividing a regular
8: 1793: 1560: 1541: 639: 137: 103: 520:, a well-known recreational mathematician and public educator, gained attention for her 1722: 1545: 1520: 1301: 1289: 1215:
The Mysterious Flexagons: An Introduction to a Fascinating New Concept in Paper Folding
1198: 1190: 1029: 997: 967: 652: 648: 583: 482: 454: 434: 404: 1309: – Scott Sherman's site, with variety of flexagons of different shapes. 601:
Anderson, Thomas; McLean, T. Bruce; Pajoohesh, Homeira; Smith, Chasen (January 2010).
145:
which then ran in that magazine for the next twenty-five years. In 1974, the magician
1629: 1500: 1298: – Robin Moseley's site has patterns for a large variety of flexagons. 1265: 1246: 1227: 1202: 1157: 1139: 1121: 1106: 1067: 1040: 683: 660: 225: 1186: 493:). Instructions for making tetra-tetra-flexagon and cross-flexagons are included in 335: 32: 1742: 1702: 1667: 1598: 1570: 1555: 1438: 1337: 1333: 1207:
The issue also contains another article by Pook, and one by Iacob, McLean, and Hua.
1182: 644: 614: 575: 506: 470: 306: 234: 112: 49: 1316: 178:
where Rogers worked, but the device, marketed as the "Hexmo", failed to catch on.
1682: 1510: 1495: 1328: 116: 1469: 310: 1752: 1727: 1717: 1697: 1692: 1575: 1408: 1358: 1090: 723: 238: 151: 132: 1712: 1353: 1350: 1325: – 1962 paper by Antony S. Conrad and Daniel K. Hartline (RIAS) 664: 619: 602: 521: 1772: 1505: 501: 264: 328: 247: 1757: 1687: 1459: 543: 514:, in which a flex was analogous to the travel between alternate universes. 314: 204: 146: 760: 344:
Once folded, faces 1, 2, and 3 are easier to find than faces 4, 5, and 6.
292: 1737: 1428: 533: 656: 1732: 1565: 1490: 942: 587: 196: 175: 120: 1093:
wrote an excellent introduction to hexaflexagons in the December 1956
916: 429: 1650: 1312: 1108:
The "Scientific American" Book of Mathematical Puzzles and Diversions
812: 579: 52:
models, usually constructed by folding strips of paper, that can be
890: 838: 446: 438: 400: 396: 124: 41: 864: 786: 224:
The tritetraflexagon is the simplest tetraflexagon (flexagon with
1346: 517: 97: 64: 208:
This figure has two faces visible, built of squares marked with
200:
A tritetraflexagon can be folded from a strip of paper as shown.
1515: 1224:
The Magic of Flexagons – Paper curiosities to cut out and make
381: 36:
A hexaflexagon, shown with the same face in two configurations
1066:. Starmont Reader's Guide #20. Borgo Press. pp. 47–48. 1031:
Making Handmade Books: 100+ Bindings, Structures & Forms
722:
Rogers, Russell E.; Andrea, Leonard D. L. (April 21, 1959).
600: 1295: 495:
Making Handmade Books: 100+ Bindings, Structures and Forms
141:
in an article so well-received that it launched Gardner's
1338:"General Solution for Multiple Foldings of Hexaflexagons" 1306: 395:
In its flat state, the pentaflexagon looks much like the
705:"The Top 10 Martin Gardner Scientific American Articles" 566:
Oakley, C. O.; Wisner, R. J. (March 1957). "Flexagons".
500:
A high-order hexaflexagon was used as a plot element in
390: 469:
Flexagons are also a popular book structure used by
574:(3). Mathematical Association of America: 143–154. 430:
Nonplanar pentaflexagon and nonplanar heptaflexagon
413: 158: 131:Flexagons were introduced to the general public by 1262:Serious Fun with Flexagons, A Compendium and Guide 1105: 1028: 1171:Gardner, Martin (January 2012). "Hexaflexagons". 1770: 1388: 163:In 1955, Russell Rogers and Leonard D'Andrea of 761:"Flexagon Discovery: The Shape-Shifting 12-Gon" 643:. Vol. 195, no. 6. pp. 162–168. 637:Gardner, Martin (December 1956). "Flexagons". 98:Discovery and introduction of the hexaflexagon 1374: 632: 630: 352:1 → 3 → 6 → 1 → 3 → 2 → 4 → 3 → 2 → 1 → 5 → 2 59:Flexagons are usually square or rectangular ( 1292:– contains historical information and theory 1053: 721: 603:"The combinatorics of all regular flexagons" 565: 724:"Changeable amusement devices and the like" 382:Right octaflexagon and right dodecaflexagon 1381: 1367: 671: 627: 618: 376: 1221: 1059: 996: 966: 943:"Enneaflexagon: Isosceles Enneaflexagon" 758: 561: 559: 334: 327: 291: 263: 246: 203: 195: 31: 1170: 940: 914: 888: 862: 836: 810: 784: 702: 677: 636: 14: 1771: 1026: 917:"Octaflexagon: Isosceles Octaflexagon" 367: 1362: 1212: 1120:. University of Chicago Press. 1988. 556: 464: 237:and in the magic wallet trick or the 1616:Geometric Exercises in Paper Folding 1259: 1240: 1156:. Cambridge University Press. 2008. 391:Pentaflexagon and right decaflexagon 255: 1637:A History of Folding in Mathematics 320: 191: 172:Herbick & Held Printing Company 24: 740:from the original on June 14, 2011 703:Mulcahy, Colm (October 21, 2014). 649:10.1038/scientificamerican1256-162 403:divided from the center into five 287: 25: 1805: 1279: 607:European Journal of Combinatorics 568:The American Mathematical Monthly 186: 1340:IJPAM, Vol. 58, No. 1, 113–124. 1329:MathWorld entry on Hexaflexagons 1136:The Colossal Book of Mathematics 1008:. Universidad AutĂłnoma de Puebla 978:. Universidad AutĂłnoma de Puebla 414:Generalized isosceles n-flexagon 275: 220:s is hidden inside the flexagon. 159:Attempted commercial development 1537:Alexandrov's uniqueness theorem 1195:10.4169/college.math.j.43.1.002 1187:10.4169/college.math.j.43.1.002 1174:The College Mathematics Journal 1138:. W. W. Norton & Co. 2001. 1084: 1020: 990: 960: 934: 908: 882: 856: 830: 682:. University of Chicago Press. 1245:. Cambridge University Press. 804: 778: 752: 715: 696: 594: 135:in the December 1956 issue of 13: 1: 1475:Regular paperfolding sequence 1112:. Simon & Schuster. 1959. 1060:Collings, Michael R. (1984). 549: 1623:Geometric Folding Algorithms 1390:Mathematics of paper folding 181: 165:Homestead Park, Pennsylvania 7: 527: 143:"Mathematical Games" column 10: 1810: 1673:Margherita Piazzola Beloch 1349:'s video on Hexaflexagons 356:And then back to 1 again. 313:whose single edge forms a 268:Hexatetraflexagon traverse 174:, the printing company in 92: 1660: 1607: 1586: 1529: 1483: 1452: 1444:Yoshizawa–Randlett system 1396: 1027:Golden, Alisa J. (2011). 620:10.1016/j.ejc.2009.01.005 251:Tritetraflexagon traverse 1644:Origami Polyhedra Design 1222:Mitchell, David (2000). 1213:Jones, Madeline (1966). 1035:. Lark Crafts. pp.  678:Gardner, Martin (1988). 1342:"19 faces of Flexagons" 1286:My Flexagon Experiences 941:Sherman, Scott (2007). 915:Sherman, Scott (2007). 889:Sherman, Scott (2007). 863:Sherman, Scott (2007). 837:Sherman, Scott (2007). 811:Sherman, Scott (2007). 785:Sherman, Scott (2007). 733:. U.S. Patent 2883195. 1789:Geometric group theory 1434:Napkin folding problem 1319:, including three nets 1101:. It also appears in: 1002:"Heptagonal Flexagons" 972:"Pentagonal Flexagons" 759:Schwartz, Ann (2005). 539:Geometric group theory 522:video on hexaflexagons 377:Higher order flexagons 341: 332: 298: 269: 252: 221: 201: 37: 731:Freepatentsonline.com 461:be made to lie flat. 338: 331: 295: 267: 250: 207: 199: 106:, while a student at 35: 1594:Fold-and-cut theorem 1550:Steffen's polyhedron 1414:Huzita–Hatori axioms 1404:Big-little-big lemma 1243:Flexagons Inside Out 108:Princeton University 87:equivalence relation 1542:Flexible polyhedron 1296:The Flexagon Portal 1217:. Crown Publishers. 1099:Scientific American 998:McIntosh, Harold V. 970:(August 24, 2000). 968:McIntosh, Harold V. 709:Scientific American 640:Scientific American 455:isosceles triangles 405:isosceles triangles 368:Other hexaflexagons 233:children's toy, in 138:Scientific American 1779:Mechanical puzzles 1723:Toshikazu Kawasaki 1546:Bricard octahedron 1521:Yoshimura buckling 1419:Kawasaki's theorem 1290:Harold V. McIntosh 1260:Pook, Les (2009). 1241:Pook, Les (2006). 1095:Mathematical Games 1000:(March 11, 2000). 483:Edward H. Hutchins 465:In popular culture 435:Harold V. McIntosh 342: 333: 299: 270: 253: 222: 202: 38: 1766: 1765: 1630:Geometric Origami 1501:Paper bag problem 1424:Maekawa's theorem 1271:978-90-481-2502-9 1163:978-0-521-73525-4 1046:978-1-60059-587-5 497:by Alisa Golden. 473:creators such as 256:Hexatetraflexagon 16:(Redirected from 1801: 1703:David A. Huffman 1668:Roger C. Alperin 1571:Source unfolding 1439:Pureland origami 1383: 1376: 1369: 1360: 1359: 1334:Yutaka Nishiyama 1275: 1256: 1237: 1218: 1206: 1167: 1149: 1131: 1113: 1111: 1078: 1077: 1057: 1051: 1050: 1034: 1024: 1018: 1017: 1015: 1013: 994: 988: 987: 985: 983: 964: 958: 957: 955: 953: 938: 932: 931: 929: 927: 912: 906: 905: 903: 901: 886: 880: 879: 877: 875: 860: 854: 853: 851: 849: 834: 828: 827: 825: 823: 813:"Dodecaflexagon" 808: 802: 801: 799: 797: 782: 776: 775: 773: 771: 765:Eighthsquare.com 756: 750: 749: 747: 745: 739: 728: 719: 713: 712: 700: 694: 693: 675: 669: 668: 634: 625: 624: 622: 598: 592: 591: 563: 511: 510: 399:logo: a regular 321:Hexahexaflexagon 307:recycling symbol 192:Tritetraflexagon 113:Bryant Tuckerman 73:hexahexaflexagon 21: 1809: 1808: 1804: 1803: 1802: 1800: 1799: 1798: 1769: 1768: 1767: 1762: 1748:Joseph O'Rourke 1683:Robert Connelly 1656: 1603: 1582: 1525: 1511:Schwarz lantern 1496:Modular origami 1479: 1448: 1392: 1387: 1282: 1272: 1253: 1234: 1164: 1152: 1146: 1134: 1128: 1116: 1104: 1087: 1082: 1081: 1074: 1058: 1054: 1047: 1025: 1021: 1011: 1009: 995: 991: 981: 979: 965: 961: 951: 949: 939: 935: 925: 923: 913: 909: 899: 897: 891:"Heptaflexagon" 887: 883: 873: 871: 861: 857: 847: 845: 839:"Pentaflexagon" 835: 831: 821: 819: 809: 805: 795: 793: 783: 779: 769: 767: 757: 753: 743: 741: 737: 726: 720: 716: 701: 697: 690: 676: 672: 635: 628: 599: 595: 580:10.2307/2310544 564: 557: 552: 530: 508: 507: 491:Voces de MĂ©xico 467: 432: 416: 393: 384: 379: 370: 323: 309:. This makes a 290: 288:Trihexaflexagon 278: 258: 216:s. The face of 194: 189: 184: 161: 117:Richard Feynman 104:Arthur H. Stone 100: 95: 28: 23: 22: 18:Trihexaflexagon 15: 12: 11: 5: 1807: 1797: 1796: 1791: 1786: 1781: 1764: 1763: 1761: 1760: 1755: 1753:Tomohiro Tachi 1750: 1745: 1740: 1735: 1730: 1728:Robert J. Lang 1725: 1720: 1718:Humiaki Huzita 1715: 1710: 1705: 1700: 1698:Rona Gurkewitz 1695: 1693:Martin Demaine 1690: 1685: 1680: 1675: 1670: 1664: 1662: 1658: 1657: 1655: 1654: 1647: 1640: 1633: 1626: 1619: 1611: 1609: 1605: 1604: 1602: 1601: 1596: 1590: 1588: 1584: 1583: 1581: 1580: 1579: 1578: 1576:Star unfolding 1573: 1568: 1563: 1553: 1539: 1533: 1531: 1527: 1526: 1524: 1523: 1518: 1513: 1508: 1503: 1498: 1493: 1487: 1485: 1481: 1480: 1478: 1477: 1472: 1467: 1462: 1456: 1454: 1450: 1449: 1447: 1446: 1441: 1436: 1431: 1426: 1421: 1416: 1411: 1409:Crease pattern 1406: 1400: 1398: 1394: 1393: 1386: 1385: 1378: 1371: 1363: 1357: 1356: 1344: 1331: 1326: 1320: 1317:tetraflexagons 1310: 1304: 1299: 1293: 1281: 1280:External links 1278: 1277: 1276: 1270: 1257: 1251: 1238: 1232: 1219: 1210: 1209: 1208: 1168: 1162: 1150: 1144: 1132: 1126: 1114: 1091:Martin Gardner 1086: 1083: 1080: 1079: 1072: 1052: 1045: 1019: 989: 959: 933: 907: 881: 865:"Decaflexagon" 855: 829: 803: 787:"Octaflexagon" 777: 751: 714: 695: 688: 670: 626: 593: 554: 553: 551: 548: 547: 546: 541: 536: 529: 526: 466: 463: 451:heptaflexagons 443:pentaflexagons 431: 428: 415: 412: 392: 389: 383: 380: 378: 375: 369: 366: 354: 353: 322: 319: 289: 286: 277: 274: 257: 254: 231:Jacob's Ladder 193: 190: 188: 187:Tetraflexagons 185: 183: 180: 160: 157: 152:The Magic Show 133:Martin Gardner 99: 96: 94: 91: 61:tetraflexagons 26: 9: 6: 4: 3: 2: 1806: 1795: 1792: 1790: 1787: 1785: 1784:Paper folding 1782: 1780: 1777: 1776: 1774: 1759: 1756: 1754: 1751: 1749: 1746: 1744: 1741: 1739: 1736: 1734: 1731: 1729: 1726: 1724: 1721: 1719: 1716: 1714: 1711: 1709: 1706: 1704: 1701: 1699: 1696: 1694: 1691: 1689: 1686: 1684: 1681: 1679: 1676: 1674: 1671: 1669: 1666: 1665: 1663: 1659: 1653: 1652: 1648: 1646: 1645: 1641: 1639: 1638: 1634: 1632: 1631: 1627: 1625: 1624: 1620: 1618: 1617: 1613: 1612: 1610: 1606: 1600: 1599:Lill's method 1597: 1595: 1592: 1591: 1589: 1587:Miscellaneous 1585: 1577: 1574: 1572: 1569: 1567: 1564: 1562: 1559: 1558: 1557: 1554: 1551: 1547: 1543: 1540: 1538: 1535: 1534: 1532: 1528: 1522: 1519: 1517: 1514: 1512: 1509: 1507: 1506:Rigid origami 1504: 1502: 1499: 1497: 1494: 1492: 1489: 1488: 1486: 1484:3d structures 1482: 1476: 1473: 1471: 1468: 1466: 1463: 1461: 1458: 1457: 1455: 1453:Strip folding 1451: 1445: 1442: 1440: 1437: 1435: 1432: 1430: 1427: 1425: 1422: 1420: 1417: 1415: 1412: 1410: 1407: 1405: 1402: 1401: 1399: 1395: 1391: 1384: 1379: 1377: 1372: 1370: 1365: 1364: 1361: 1355: 1352: 1348: 1345: 1343: 1339: 1335: 1332: 1330: 1327: 1324: 1321: 1318: 1314: 1311: 1308: 1305: 1303: 1300: 1297: 1294: 1291: 1287: 1284: 1283: 1273: 1267: 1263: 1258: 1254: 1252:0-521-81970-9 1248: 1244: 1239: 1235: 1233:1-899618-28-7 1229: 1225: 1220: 1216: 1211: 1204: 1200: 1196: 1192: 1188: 1184: 1180: 1176: 1175: 1169: 1165: 1159: 1155: 1151: 1147: 1145:0-393-02023-1 1141: 1137: 1133: 1129: 1127:0-226-28254-6 1123: 1119: 1115: 1110: 1109: 1103: 1102: 1100: 1096: 1092: 1089: 1088: 1075: 1073:0-89370-058-4 1069: 1065: 1064: 1063:Piers Anthony 1056: 1048: 1042: 1038: 1033: 1032: 1023: 1007: 1003: 999: 993: 977: 973: 969: 963: 948: 944: 937: 922: 918: 911: 896: 892: 885: 870: 866: 859: 844: 840: 833: 818: 814: 807: 792: 788: 781: 766: 762: 755: 736: 732: 725: 718: 710: 706: 699: 691: 689:0-226-28254-6 685: 681: 674: 666: 662: 658: 654: 650: 646: 642: 641: 633: 631: 621: 616: 612: 608: 604: 597: 589: 585: 581: 577: 573: 569: 562: 560: 555: 545: 542: 540: 537: 535: 532: 531: 525: 523: 519: 515: 513: 512: 503: 502:Piers Anthony 498: 496: 492: 488: 484: 480: 476: 472: 471:artist's book 462: 460: 456: 452: 448: 444: 440: 436: 427: 425: 421: 411: 408: 406: 402: 398: 388: 374: 365: 361: 357: 351: 350: 349: 345: 337: 330: 326: 318: 316: 312: 308: 303: 294: 285: 283: 282:hexaflexagons 276:Hexaflexagons 273: 266: 262: 249: 245: 242: 240: 236: 235:Rubik's Magic 232: 227: 219: 215: 211: 206: 198: 179: 177: 173: 168: 166: 156: 154: 153: 148: 144: 140: 139: 134: 129: 126: 122: 118: 114: 109: 105: 90: 88: 83: 81: 76: 74: 70: 69:hexaflexagons 66: 62: 57: 55: 51: 47: 43: 34: 30: 19: 1758:Eve Torrence 1688:Erik Demaine 1649: 1642: 1635: 1628: 1621: 1614: 1608:Publications 1470:Möbius strip 1464: 1460:Dragon curve 1397:Flat folding 1264:. Springer. 1261: 1242: 1223: 1214: 1178: 1172: 1153: 1135: 1117: 1107: 1098: 1094: 1085:Bibliography 1062: 1055: 1030: 1022: 1010:. Retrieved 1006:Cinvestav.mx 1005: 992: 980:. Retrieved 976:Cinvestav.mx 975: 962: 950:. Retrieved 946: 936: 924:. Retrieved 920: 910: 898:. Retrieved 894: 884: 872:. Retrieved 868: 858: 846:. Retrieved 842: 832: 820:. Retrieved 816: 806: 794:. Retrieved 790: 780: 768:. Retrieved 764: 754: 742:. Retrieved 730: 717: 708: 698: 679: 673: 638: 613:(1): 72–80. 610: 606: 596: 571: 567: 544:Kaleidocycle 516: 505: 499: 494: 490: 486: 478: 468: 458: 450: 442: 433: 423: 419: 417: 409: 394: 385: 371: 362: 358: 355: 346: 343: 324: 315:trefoil knot 311:Möbius strip 304: 300: 281: 279: 271: 259: 243: 223: 217: 213: 209: 169: 162: 150: 147:Doug Henning 136: 130: 101: 84: 79: 77: 72: 68: 60: 58: 53: 45: 39: 29: 1743:KĹŤryĹŤ Miura 1738:Jun Maekawa 1713:KĂ´di Husimi 1429:Map folding 1315:'s page on 1226:. Tarquin. 1039:, 132–133. 1012:October 26, 982:October 26, 952:October 26, 926:October 26, 900:October 26, 874:October 26, 848:October 26, 822:October 26, 796:October 26, 770:October 26, 744:January 13, 534:Cayley tree 457:, and they 445:, and from 125:topological 27:Paper model 1794:Paper toys 1773:Categories 1733:Anna Lubiw 1566:Common net 1491:Miura fold 1181:(1): 2–5. 1097:column in 665:4657622161 550:References 479:Life Cycle 475:Julie Chen 422:-gon into 176:Pittsburgh 121:John Tukey 1651:Origamics 1530:Polyhedra 1323:Flexagons 1313:MathWorld 1307:Flexagons 1302:Flexagons 1203:218544330 947:Loki3.com 921:Loki3.com 895:Loki3.com 869:Loki3.com 843:Loki3.com 817:Loki3.com 791:Loki3.com 504:'s novel 447:heptagons 439:pentagons 182:Varieties 65:hexagonal 46:flexagons 1708:Tom Hull 1678:Yan Chen 1561:Blooming 1465:Flexagon 1336:(2010). 735:Archived 657:24941843 528:See also 401:pentagon 397:Chrysler 241:wallet. 42:geometry 1347:Vi Hart 588:2310544 518:Vi Hart 449:called 441:called 297:folded. 93:History 1661:People 1516:Sonobe 1354:part 2 1351:part 1 1268:  1249:  1230:  1201:  1193:  1160:  1142:  1124:  1070:  1043:  686:  663:  655:  586:  481:) and 239:Himber 226:square 212:s and 119:, and 54:flexed 1199:S2CID 1191:JSTOR 738:(PDF) 727:(PDF) 653:JSTOR 584:JSTOR 487:Album 63:) or 1266:ISBN 1247:ISBN 1228:ISBN 1158:ISBN 1140:ISBN 1122:ISBN 1068:ISBN 1041:ISBN 1014:2012 984:2012 954:2012 928:2012 902:2012 876:2012 850:2012 824:2012 798:2012 772:2012 746:2011 684:ISBN 661:OCLC 489:and 80:pats 50:flat 48:are 1556:Net 1288:by 1183:doi 1037:130 645:doi 615:doi 576:doi 459:can 40:In 1775:: 1548:, 1197:. 1189:. 1179:43 1177:. 1004:. 974:. 945:. 919:. 893:. 867:. 841:. 815:. 789:. 763:. 729:. 707:. 659:. 651:. 629:^ 611:31 609:. 605:. 582:. 572:64 570:. 558:^ 524:. 509:0X 317:. 155:. 115:, 89:. 82:. 75:. 44:, 1552:) 1544:( 1382:e 1375:t 1368:v 1274:. 1255:. 1236:. 1205:. 1185:: 1166:. 1148:. 1130:. 1076:. 1049:. 1016:. 986:. 956:. 930:. 904:. 878:. 852:. 826:. 800:. 774:. 748:. 711:. 692:. 667:. 647:: 623:. 617:: 590:. 578:: 485:( 477:( 424:n 420:n 218:C 214:B 210:A 67:( 20:)

Index

Trihexaflexagon
A hexaflexagon, shown with the same face in two configurations
geometry
flat
hexagonal
equivalence relation
Arthur H. Stone
Princeton University
Bryant Tuckerman
Richard Feynman
John Tukey
topological
Martin Gardner
Scientific American
"Mathematical Games" column
Doug Henning
The Magic Show
Homestead Park, Pennsylvania
Herbick & Held Printing Company
Pittsburgh
Diagram for folding a tritetraflexagon
Sides of a tritetraflexagon
square
Jacob's Ladder
Rubik's Magic
Himber



recycling symbol

Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.

↑