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Flexagon

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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.
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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.)
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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,
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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
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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
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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
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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
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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.
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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
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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.
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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.)
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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.
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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:
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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
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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
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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
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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."
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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.
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Hexaflexagons come in great variety, distinguished by the number of faces that can be achieved by flexing the assembled figure. (Note that the word
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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.
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folded, eliminating some faces. Many strips can be folded in different ways, producing different hexaflexagons, with different folding maps.
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To assemble, the strip is folded every third triangle, connecting back to itself after three inversions in the manner of the international
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octaflexagons, and the division of the triangular faces of the hexaflexagons into 30-60-90 right triangles yields the dodecaflexagons.
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Two flexagons are equivalent if one can be transformed to the other by a series of pinches and rotations. Flexagon equivalence is an
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Hexaflexagons, Probability Paradoxes, and the Tower of Hanoi: Martin Gardner's First Book of Mathematical Puzzles and Games
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isosceles triangles. Other flexagons include the heptaflexagon, the isosceles octaflexagon, the enneaflexagon, and others.
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Contrary to the tritetraflexagon, the hexatetraflexagon has no dead ends, and does not ever need to be flexed backwards.
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In hexaflexagon theory (that is, concerning flexagons with six sides), flexagons are usually defined in terms of
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also describes "nonplanar" flexagons (i.e., ones which cannot be flexed so they lie flat); ones folded from
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Hexaflexagons and Other Mathematical Diversions: The First "Scientific American" Book of Puzzles and Games
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Hexaflexagons and Other Mathematical Diversions: The First Scientific American Book of Puzzles and Games
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or folded in certain ways to reveal faces besides the two that were originally on the back and front.
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This hexaflexagon has six faces. It is made up of nineteen triangles folded from a strip of paper.
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became interested in the idea and formed the Princeton Flexagon Committee. Tuckerman worked out a
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included a construct-your-own hexaflexagon with the original cast recording of his Broadway show
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The discovery of the first flexagon, a trihexaflexagon, is credited to the British mathematician
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can sometimes refer to an ordinary hexahexaflexagon, with six sides instead of other numbers.)
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The pentaflexagon is one of an infinite sequence of flexagons based on dividing a regular
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The Mysterious Flexagons: An Introduction to a Fascinating New Concept in Paper Folding
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Anderson, Thomas; McLean, T. Bruce; Pajoohesh, Homeira; Smith, Chasen (January 2010).
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which then ran in that magazine for the next twenty-five years. In 1974, the magician
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The issue also contains another article by Pook, and one by Iacob, McLean, and Hua.
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where Rogers worked, but the device, marketed as the "Hexmo", failed to catch on.
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Once folded, faces 1, 2, and 3 are easier to find than faces 4, 5, and 6.
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wrote an excellent introduction to hexaflexagons in the December 1956
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The "Scientific American" Book of Mathematical Puzzles and Diversions
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models, usually constructed by folding strips of paper, that can be
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The tritetraflexagon is the simplest tetraflexagon (flexagon with
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This figure has two faces visible, built of squares marked with
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A tritetraflexagon can be folded from a strip of paper as shown.
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The Magic of Flexagons – Paper curiosities to cut out and make
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A hexaflexagon, shown with the same face in two configurations
1055:. Starmont Reader's Guide #20. Borgo Press. pp. 47–48. 1020:
Making Handmade Books: 100+ Bindings, Structures & Forms
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Rogers, Russell E.; Andrea, Leonard D. L. (April 21, 1959).
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Making Handmade Books: 100+ Bindings, Structures and Forms
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in an article so well-received that it launched Gardner's
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In its flat state, the pentaflexagon looks much like the
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Oakley, C. O.; Wisner, R. J. (March 1957). "Flexagons".
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A high-order hexaflexagon was used as a plot element in
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Flexagons are also a popular book structure used by
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Nonplanar pentaflexagon and nonplanar heptaflexagon
402: 147: 120:Flexagons were introduced to the general public by 1251:Serious Fun with Flexagons, A Compendium and Guide 1094: 1017: 1160:Gardner, Martin (January 2012). "Hexaflexagons". 1759: 1377: 152:In 1955, Russell Rogers and Leonard D'Andrea of 750:"Flexagon Discovery: The Shape-Shifting 12-Gon" 632:. Vol. 195, no. 6. pp. 162–168. 626:Gardner, Martin (December 1956). "Flexagons". 87:Discovery and introduction of the hexaflexagon 1363: 621: 619: 341:1 → 3 → 6 → 1 → 3 → 2 → 4 → 3 → 2 → 1 → 5 → 2 48:Flexagons are usually square or rectangular ( 1281:– contains historical information and theory 1042: 710: 592:"The combinatorics of all regular flexagons" 554: 713:"Changeable amusement devices and the like" 371:Right octaflexagon and right dodecaflexagon 1370: 1356: 660: 616: 607: 365: 1210: 1048: 985: 955: 932:"Enneaflexagon: Isosceles Enneaflexagon" 747: 550: 548: 323: 316: 280: 252: 235: 192: 184: 20: 1159: 929: 903: 877: 851: 825: 799: 773: 691: 666: 625: 1760: 1015: 906:"Octaflexagon: Isosceles Octaflexagon" 356: 1351: 1201: 1109:. University of Chicago Press. 1988. 545: 453: 226:and in the magic wallet trick or the 1605:Geometric Exercises in Paper Folding 1248: 1229: 1145:. Cambridge University Press. 2008. 380:Pentaflexagon and right decaflexagon 244: 1626:A History of Folding in Mathematics 309: 180: 161:Herbick & Held Printing Company 13: 729:from the original on June 14, 2011 692:Mulcahy, Colm (October 21, 2014). 638:10.1038/scientificamerican1256-162 392:divided from the center into five 276: 14: 1794: 1268: 596:European Journal of Combinatorics 557:The American Mathematical Monthly 175: 1329:IJPAM, Vol. 58, No. 1, 113–124. 1318:MathWorld entry on Hexaflexagons 1125:The Colossal Book of Mathematics 997:. Universidad AutĂłnoma de Puebla 967:. Universidad AutĂłnoma de Puebla 403:Generalized isosceles n-flexagon 264: 209:s is hidden inside the flexagon. 148:Attempted commercial development 1526:Alexandrov's uniqueness theorem 1184:10.4169/college.math.j.43.1.002 1176:10.4169/college.math.j.43.1.002 1163:The College Mathematics Journal 1127:. W. W. Norton & Co. 2001. 1073: 1009: 979: 949: 923: 897: 871: 845: 819: 671:. University of Chicago Press. 1234:. Cambridge University Press. 793: 767: 741: 704: 685: 583: 124:in the December 1956 issue of 1: 1464:Regular paperfolding sequence 1101:. Simon & Schuster. 1959. 1049:Collings, Michael R. (1984). 538: 1612:Geometric Folding Algorithms 1379:Mathematics of paper folding 170: 154:Homestead Park, Pennsylvania 7: 516: 132:"Mathematical Games" column 10: 1799: 1662:Margherita Piazzola Beloch 1338:'s video on Hexaflexagons 345:And then back to 1 again. 302:whose single edge forms a 257:Hexatetraflexagon traverse 163:, the printing company in 81: 1649: 1596: 1575: 1518: 1472: 1441: 1433:Yoshizawa–Randlett system 1385: 1016:Golden, Alisa J. (2011). 609:10.1016/j.ejc.2009.01.005 240:Tritetraflexagon traverse 1633:Origami Polyhedra Design 1211:Mitchell, David (2000). 1202:Jones, Madeline (1966). 1024:. Lark Crafts. pp.  667:Gardner, Martin (1988). 1331:"19 faces of Flexagons" 1275:My Flexagon Experiences 930:Sherman, Scott (2007). 904:Sherman, Scott (2007). 878:Sherman, Scott (2007). 852:Sherman, Scott (2007). 826:Sherman, Scott (2007). 800:Sherman, Scott (2007). 774:Sherman, Scott (2007). 722:. U.S. Patent 2883195. 1778:Geometric group theory 1423:Napkin folding problem 1308:, including three nets 1090:. It also appears in: 991:"Heptagonal Flexagons" 961:"Pentagonal Flexagons" 748:Schwartz, Ann (2005). 528:Geometric group theory 511:video on hexaflexagons 366:Higher order flexagons 330: 321: 287: 258: 241: 210: 190: 26: 720:Freepatentsonline.com 450:be made to lie flat. 327: 320: 284: 256: 239: 196: 188: 95:, while a student at 24: 1583:Fold-and-cut theorem 1539:Steffen's polyhedron 1403:Huzita–Hatori axioms 1393:Big-little-big lemma 1232:Flexagons Inside Out 97:Princeton University 76:equivalence relation 1531:Flexible polyhedron 1285:The Flexagon Portal 1206:. Crown Publishers. 1088:Scientific American 987:McIntosh, Harold V. 959:(August 24, 2000). 957:McIntosh, Harold V. 698:Scientific American 629:Scientific American 444:isosceles triangles 394:isosceles triangles 357:Other hexaflexagons 222:children's toy, in 127:Scientific American 1768:Mechanical puzzles 1712:Toshikazu Kawasaki 1535:Bricard octahedron 1510:Yoshimura buckling 1408:Kawasaki's theorem 1279:Harold V. McIntosh 1249:Pook, Les (2009). 1230:Pook, Les (2006). 1084:Mathematical Games 989:(March 11, 2000). 472:Edward H. Hutchins 454:In popular culture 424:Harold V. McIntosh 331: 322: 288: 259: 242: 211: 191: 27: 1755: 1754: 1619:Geometric Origami 1490:Paper bag problem 1413:Maekawa's theorem 1260:978-90-481-2502-9 1152:978-0-521-73525-4 1035:978-1-60059-587-5 486:by Alisa Golden. 462:creators such as 245:Hexatetraflexagon 1790: 1692:David A. Huffman 1657:Roger C. Alperin 1560:Source unfolding 1428:Pureland origami 1372: 1365: 1358: 1349: 1348: 1323:Yutaka Nishiyama 1264: 1245: 1226: 1207: 1195: 1156: 1138: 1120: 1102: 1100: 1067: 1066: 1046: 1040: 1039: 1023: 1013: 1007: 1006: 1004: 1002: 983: 977: 976: 974: 972: 953: 947: 946: 944: 942: 927: 921: 920: 918: 916: 901: 895: 894: 892: 890: 875: 869: 868: 866: 864: 849: 843: 842: 840: 838: 823: 817: 816: 814: 812: 802:"Dodecaflexagon" 797: 791: 790: 788: 786: 771: 765: 764: 762: 760: 754:Eighthsquare.com 745: 739: 738: 736: 734: 728: 717: 708: 702: 701: 689: 683: 682: 664: 658: 657: 623: 614: 613: 611: 587: 581: 580: 552: 500: 499: 388:logo: a regular 310:Hexahexaflexagon 296:recycling symbol 181:Tritetraflexagon 102:Bryant Tuckerman 62:hexahexaflexagon 1798: 1797: 1793: 1792: 1791: 1789: 1788: 1787: 1758: 1757: 1756: 1751: 1737:Joseph O'Rourke 1672:Robert Connelly 1645: 1592: 1571: 1514: 1500:Schwarz lantern 1485:Modular origami 1468: 1437: 1381: 1376: 1271: 1261: 1242: 1223: 1153: 1141: 1135: 1123: 1117: 1105: 1093: 1076: 1071: 1070: 1063: 1047: 1043: 1036: 1014: 1010: 1000: 998: 984: 980: 970: 968: 954: 950: 940: 938: 928: 924: 914: 912: 902: 898: 888: 886: 880:"Heptaflexagon" 876: 872: 862: 860: 850: 846: 836: 834: 828:"Pentaflexagon" 824: 820: 810: 808: 798: 794: 784: 782: 772: 768: 758: 756: 746: 742: 732: 730: 726: 715: 709: 705: 690: 686: 679: 665: 661: 624: 617: 588: 584: 569:10.2307/2310544 553: 546: 541: 519: 497: 496: 480:Voces de MĂ©xico 456: 421: 405: 382: 373: 368: 359: 312: 298:. This makes a 279: 277:Trihexaflexagon 267: 247: 205:s. The face of 183: 178: 173: 150: 106:Richard Feynman 93:Arthur H. Stone 89: 84: 17: 12: 11: 5: 1796: 1786: 1785: 1780: 1775: 1770: 1753: 1752: 1750: 1749: 1744: 1742:Tomohiro Tachi 1739: 1734: 1729: 1724: 1719: 1717:Robert J. Lang 1714: 1709: 1707:Humiaki Huzita 1704: 1699: 1694: 1689: 1687:Rona Gurkewitz 1684: 1682:Martin Demaine 1679: 1674: 1669: 1664: 1659: 1653: 1651: 1647: 1646: 1644: 1643: 1636: 1629: 1622: 1615: 1608: 1600: 1598: 1594: 1593: 1591: 1590: 1585: 1579: 1577: 1573: 1572: 1570: 1569: 1568: 1567: 1565:Star unfolding 1562: 1557: 1552: 1542: 1528: 1522: 1520: 1516: 1515: 1513: 1512: 1507: 1502: 1497: 1492: 1487: 1482: 1476: 1474: 1470: 1469: 1467: 1466: 1461: 1456: 1451: 1445: 1443: 1439: 1438: 1436: 1435: 1430: 1425: 1420: 1415: 1410: 1405: 1400: 1398:Crease pattern 1395: 1389: 1387: 1383: 1382: 1375: 1374: 1367: 1360: 1352: 1346: 1345: 1333: 1320: 1315: 1309: 1306:tetraflexagons 1299: 1293: 1288: 1282: 1270: 1269:External links 1267: 1266: 1265: 1259: 1246: 1240: 1227: 1221: 1208: 1199: 1198: 1197: 1157: 1151: 1139: 1133: 1121: 1115: 1103: 1080:Martin Gardner 1075: 1072: 1069: 1068: 1061: 1041: 1034: 1008: 978: 948: 922: 896: 870: 854:"Decaflexagon" 844: 818: 792: 776:"Octaflexagon" 766: 740: 703: 684: 677: 659: 615: 582: 543: 542: 540: 537: 536: 535: 530: 525: 518: 515: 455: 452: 440:heptaflexagons 432:pentaflexagons 420: 417: 404: 401: 381: 378: 372: 369: 367: 364: 358: 355: 343: 342: 311: 308: 278: 275: 266: 263: 246: 243: 220:Jacob's Ladder 182: 179: 177: 176:Tetraflexagons 174: 172: 169: 149: 146: 141:The Magic Show 122:Martin Gardner 88: 85: 83: 80: 50:tetraflexagons 15: 9: 6: 4: 3: 2: 1795: 1784: 1781: 1779: 1776: 1774: 1773:Paper folding 1771: 1769: 1766: 1765: 1763: 1748: 1745: 1743: 1740: 1738: 1735: 1733: 1730: 1728: 1725: 1723: 1720: 1718: 1715: 1713: 1710: 1708: 1705: 1703: 1700: 1698: 1695: 1693: 1690: 1688: 1685: 1683: 1680: 1678: 1675: 1673: 1670: 1668: 1665: 1663: 1660: 1658: 1655: 1654: 1652: 1648: 1642: 1641: 1637: 1635: 1634: 1630: 1628: 1627: 1623: 1621: 1620: 1616: 1614: 1613: 1609: 1607: 1606: 1602: 1601: 1599: 1595: 1589: 1588:Lill's method 1586: 1584: 1581: 1580: 1578: 1576:Miscellaneous 1574: 1566: 1563: 1561: 1558: 1556: 1553: 1551: 1548: 1547: 1546: 1543: 1540: 1536: 1532: 1529: 1527: 1524: 1523: 1521: 1517: 1511: 1508: 1506: 1503: 1501: 1498: 1496: 1495:Rigid origami 1493: 1491: 1488: 1486: 1483: 1481: 1478: 1477: 1475: 1473:3d structures 1471: 1465: 1462: 1460: 1457: 1455: 1452: 1450: 1447: 1446: 1444: 1442:Strip folding 1440: 1434: 1431: 1429: 1426: 1424: 1421: 1419: 1416: 1414: 1411: 1409: 1406: 1404: 1401: 1399: 1396: 1394: 1391: 1390: 1388: 1384: 1380: 1373: 1368: 1366: 1361: 1359: 1354: 1353: 1350: 1344: 1341: 1337: 1334: 1332: 1328: 1324: 1321: 1319: 1316: 1313: 1310: 1307: 1303: 1300: 1297: 1294: 1292: 1289: 1286: 1283: 1280: 1276: 1273: 1272: 1262: 1256: 1252: 1247: 1243: 1241:0-521-81970-9 1237: 1233: 1228: 1224: 1222:1-899618-28-7 1218: 1214: 1209: 1205: 1200: 1193: 1189: 1185: 1181: 1177: 1173: 1169: 1165: 1164: 1158: 1154: 1148: 1144: 1140: 1136: 1134:0-393-02023-1 1130: 1126: 1122: 1118: 1116:0-226-28254-6 1112: 1108: 1104: 1099: 1098: 1092: 1091: 1089: 1085: 1081: 1078: 1077: 1064: 1062:0-89370-058-4 1058: 1054: 1053: 1052:Piers Anthony 1045: 1037: 1031: 1027: 1022: 1021: 1012: 996: 992: 988: 982: 966: 962: 958: 952: 937: 933: 926: 911: 907: 900: 885: 881: 874: 859: 855: 848: 833: 829: 822: 807: 803: 796: 781: 777: 770: 755: 751: 744: 725: 721: 714: 707: 699: 695: 688: 680: 678:0-226-28254-6 674: 670: 663: 655: 651: 647: 643: 639: 635: 631: 630: 622: 620: 610: 605: 601: 597: 593: 586: 578: 574: 570: 566: 562: 558: 551: 549: 544: 534: 531: 529: 526: 524: 521: 520: 514: 512: 508: 504: 502: 501: 492: 491:Piers Anthony 487: 485: 481: 477: 473: 469: 465: 461: 460:artist's book 451: 449: 445: 441: 437: 433: 429: 425: 416: 414: 410: 400: 397: 395: 391: 387: 377: 363: 354: 350: 346: 340: 339: 338: 334: 326: 319: 315: 307: 305: 301: 297: 292: 283: 274: 272: 271:hexaflexagons 265:Hexaflexagons 262: 255: 251: 238: 234: 231: 229: 225: 224:Rubik's Magic 221: 216: 208: 204: 200: 195: 187: 168: 166: 162: 157: 155: 145: 143: 142: 137: 133: 129: 128: 123: 118: 115: 111: 107: 103: 98: 94: 79: 77: 72: 70: 65: 63: 59: 58:hexaflexagons 55: 51: 46: 44: 40: 36: 32: 23: 19: 1747:Eve Torrence 1677:Erik Demaine 1638: 1631: 1624: 1617: 1610: 1603: 1597:Publications 1459:Möbius strip 1453: 1449:Dragon curve 1386:Flat folding 1253:. Springer. 1250: 1231: 1212: 1203: 1167: 1161: 1142: 1124: 1106: 1096: 1087: 1083: 1074:Bibliography 1051: 1044: 1019: 1011: 999:. Retrieved 995:Cinvestav.mx 994: 981: 969:. Retrieved 965:Cinvestav.mx 964: 951: 939:. Retrieved 935: 925: 913:. Retrieved 909: 899: 887:. Retrieved 883: 873: 861:. Retrieved 857: 847: 835:. Retrieved 831: 821: 809:. Retrieved 805: 795: 783:. Retrieved 779: 769: 757:. Retrieved 753: 743: 731:. Retrieved 719: 706: 697: 687: 668: 662: 627: 602:(1): 72–80. 599: 595: 585: 560: 556: 533:Kaleidocycle 505: 494: 488: 483: 479: 475: 467: 457: 447: 439: 431: 422: 412: 408: 406: 398: 383: 374: 360: 351: 347: 344: 335: 332: 313: 304:trefoil knot 300:Möbius strip 293: 289: 270: 268: 260: 248: 232: 212: 206: 202: 198: 158: 151: 139: 136:Doug Henning 125: 119: 90: 73: 68: 66: 61: 57: 49: 47: 42: 34: 28: 18: 1732:KĹŤryĹŤ Miura 1727:Jun Maekawa 1702:KĂ´di Husimi 1418:Map folding 1304:'s page on 1215:. Tarquin. 1028:, 132–133. 1001:October 26, 971:October 26, 941:October 26, 915:October 26, 889:October 26, 863:October 26, 837:October 26, 811:October 26, 785:October 26, 759:October 26, 733:January 13, 523:Cayley tree 446:, and they 434:, and from 114:topological 16:Paper model 1783:Paper toys 1762:Categories 1722:Anna Lubiw 1555:Common net 1480:Miura fold 1170:(1): 2–5. 1086:column in 654:4657622161 539:References 468:Life Cycle 464:Julie Chen 411:-gon into 165:Pittsburgh 110:John Tukey 1640:Origamics 1519:Polyhedra 1312:Flexagons 1302:MathWorld 1296:Flexagons 1291:Flexagons 1192:218544330 936:Loki3.com 910:Loki3.com 884:Loki3.com 858:Loki3.com 832:Loki3.com 806:Loki3.com 780:Loki3.com 493:'s novel 436:heptagons 428:pentagons 171:Varieties 54:hexagonal 35:flexagons 1697:Tom Hull 1667:Yan Chen 1550:Blooming 1454:Flexagon 1325:(2010). 724:Archived 646:24941843 517:See also 390:pentagon 386:Chrysler 230:wallet. 31:geometry 1336:Vi Hart 577:2310544 507:Vi Hart 438:called 430:called 286:folded. 82:History 1650:People 1505:Sonobe 1343:part 2 1340:part 1 1257:  1238:  1219:  1190:  1182:  1149:  1131:  1113:  1059:  1032:  675:  652:  644:  575:  470:) and 228:Himber 215:square 201:s and 108:, and 43:flexed 1188:S2CID 1180:JSTOR 727:(PDF) 716:(PDF) 642:JSTOR 573:JSTOR 476:Album 52:) or 1255:ISBN 1236:ISBN 1217:ISBN 1147:ISBN 1129:ISBN 1111:ISBN 1057:ISBN 1030:ISBN 1003:2012 973:2012 943:2012 917:2012 891:2012 865:2012 839:2012 813:2012 787:2012 761:2012 735:2011 673:ISBN 650:OCLC 478:and 69:pats 39:flat 37:are 1545:Net 1277:by 1172:doi 1026:130 634:doi 604:doi 565:doi 448:can 29:In 1764:: 1537:, 1186:. 1178:. 1168:43 1166:. 993:. 963:. 934:. 908:. 882:. 856:. 830:. 804:. 778:. 752:. 718:. 696:. 648:. 640:. 618:^ 600:31 598:. 594:. 571:. 561:64 559:. 547:^ 513:. 498:0X 306:. 144:. 104:, 78:. 71:. 64:. 33:, 1541:) 1533:( 1371:e 1364:t 1357:v 1263:. 1244:. 1225:. 1194:. 1174:: 1155:. 1137:. 1119:. 1065:. 1038:. 1005:. 975:. 945:. 919:. 893:. 867:. 841:. 815:. 789:. 763:. 737:. 700:. 681:. 656:. 636:: 612:. 606:: 579:. 567:: 474:( 466:( 413:n 409:n 207:C 203:B 199:A 56:(

Index

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
Möbius strip

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