Knowledge (XXG)

Icosahedron

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with its 6 square faces bisected on diagonals with pyritohedral symmetry. The icosahedra with pyritohedral symmetry constitute an infinite family of polyhedra which include the cuboctahedron, regular icosahedron, Jessen's icosahedron, and
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is the process of extending the faces or edges of a polyhedron until they meet to form a new polyhedron. It is done symmetrically so that the resulting figure retains the overall symmetry of the parent figure.
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has the symbol (332), , with order 12. These lower symmetries allow geometric distortions from 20 equilateral triangular faces, instead having 8 equilateral triangles and 12 congruent
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of the 12 vertices can be defined by the vectors defined by all the possible cyclic permutations and sign-flips of coordinates of the form (2, 1, 0). These coordinates represent the
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Other stellations have more than one face in each plane or form compounds of simpler polyhedra. These are not strictly icosahedra, although they are often referred to as such.
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rather than a pentagon, leading to geometrically intersecting faces. The intersections of the triangles do not represent new edges.
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Of these, many have a single face in each of the 20 face planes and so are also icosahedra. The great icosahedron is among them.
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There are two objects, one convex and one nonconvex, that can both be called regular icosahedra. Each has 30 edges and 20
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to a cube, meaning that it can be sliced into smaller polyhedral pieces that can be rearranged to form a solid cube.
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in its regular icosahedron form, generated by the same operations carried out starting with the vector (
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by removing 10 middle faces. Even though all the faces are congruent, the rhombic icosahedron is not
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shapes of icosahedra, some of them being more symmetrical than others. The best known is the (
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with its 6 square faces bisected on diagonals with pyritohedral symmetry. There exists a
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octahedron. Cyclical kinematic transformations among the members of this family exist.
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Koca, Nazife; Al-Mukhaini, Aida; Koca, Mehmet; Al Qanobi, Amal (2016-12-01).
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The stellation process on the icosahedron creates a number of related
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The convex regular icosahedron is usually referred to simply as the
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faces with five meeting at each of its twelve vertices. Both have
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kinematic transformation between cuboctahedron and icosahedron
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Common icosahedra with pyramid and prism symmetries include:
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made up of 20 congruent rhombs. It can be derived from the
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respectively, each representing the lower symmetry to the
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Connections: The Geometric Bridge Between Art and Science
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A regular icosahedron is topologically identical to a
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A regular icosahedron is topologically identical to a
820: 811: 197: 'seat'. The plural can be either "icosahedra" ( 146: 140: 137: 117: 108: 81: 75: 69: 1375: 470: 206: 203: 164: 161: 99: 96: 2423: 2398: 2373: 2348: 2264: 2172: 2127: 2037: 2008: 1973: 1921: 1862: 1801: 1740: 844:{\displaystyle s{\begin{Bmatrix}3\\3\end{Bmatrix}}} 155: 152: 90: 87: 843: 326:inscribed in a con­vex regular icosahedron 1676:(2nd ed.). World Scientific. p. 475. 2104: 1711: 1625:Sultan Qaboos University Journal for Science 8: 956: 1621:"Symmetry of the Pyritohedron and Lattices" 716: 2377: 2111: 2097: 2089: 1718: 1704: 1696: 1214:In Jessen's icosahedron, sometimes called 1636: 1599:, Cambridge: Cambridge University Press, 1509: 1397: 998:can be distorted or marked up as a lower 815: 810: 717:Pyritohedral and tetrahedral symmetries 1584: 1035:has the symbol (3*2), , with order 24. 179:with 20 faces. The name comes from 1650: 1648: 7: 1153:Construction from the vertices of a 1735:Listed by number of faces and type 1417:Elongated triangular orthobicupola 1346:(2 sets of 9 sides + 2 ends = 20). 25: 1638:10.24200/squjs.vol21iss2pp139-149 1428:Elongated triangular gyrobicupola 1655:John Baez (September 11, 2011). 1502: 1495: 1488: 1481: 1474: 1467: 1454: 1443: 1432: 1421: 1410: 1399: 1131: 1126: 1121: 1116: 1111: 1100: 1095: 1090: 1085: 1080: 1072: 1067: 1062: 1057: 1052: 967: 960: 943: 789: 782: 777: 772: 767: 762: 755: 748: 743: 738: 733: 728: 682: 675: 668: 661: 654: 647: 640: 633: 626: 617: 610: 603: 596: 589: 582: 575: 568: 561: 386:is one of the four regular star 276: 261: 199: 130: 65: 1406:Gyroelongated triangular cupola 1258:Kinematics of the cuboctahedron 1216:Jessen's orthogonal icosahedron 932: 920: 904: 888: 878: 868: 854: 797: 721: 255:Two kinds of regular icosahedra 1597:English Pronouncing Dictionary 1176:This construction is called a 1157:, showing internal rectangles. 477:stellations of the icosahedron 220:There are infinitely many non- 1: 1946:(two infinite groups and 75) 2491:Degenerate polyhedra are in 1964:(two infinite groups and 50) 1461:Triangular hebesphenorotunda 1450:Metabiaugmented dodecahedron 1439:Parabiaugmented dodecahedron 1320:Pyramid and prism symmetries 423:great stellated dodecahedron 338:, and is represented by its 2310:pentagonal icositetrahedron 2251:truncated icosidodecahedron 1195: 1025:. If all the triangles are 535:Compound of five tetrahedra 520:Medial triambic icosahedron 190: 'twenty' and 2534: 2340:pentagonal hexecontahedron 2300:deltoidal icositetrahedron 1360:(2 sets of 10 sides = 20). 1353:(2 sets of 10 sides = 20). 1293: 1255: 1207: 1002:symmetry, and is called a 690: 540:Compound of ten tetrahedra 530:Compound of five octahedra 525:Great triambic icosahedron 515:Small triambic icosahedron 473: 360: 334:, one of the five regular 311: 308:Convex regular icosahedron 2489: 2380: 2335:disdyakis triacontahedron 2330:deltoidal hexecontahedron 2016:Kepler–Poinsot polyhedron 1733: 1018:. This can be seen as an 975: 955: 942: 639: 574: 503: 493: 488: 459:The Fifty-Nine Icosahedra 1244:Progressions between an 388:Kepler-Poinsot polyhedra 29:Polyhedron with 20 faces 2441:gyroelongated bipyramid 2315:rhombic triacontahedron 2221:truncated cuboctahedron 2028:Uniform star polyhedron 1956:quasiregular polyhedron 1310:rhombic triacontahedron 1046:These symmetries offer 874:30 (6 short + 24 long) 2436:truncated trapezohedra 2305:disdyakis dodecahedron 2271:(duals of Archimedean) 2246:rhombicosidodecahedron 2236:truncated dodecahedron 1962:semiregular polyhedron 1670:Kappraff, Jay (1991). 1286: 1253: 1205: 1158: 845: 550:Excavated dodecahedron 379: 327: 52: 40: 2325:pentakis dodecahedron 2241:truncated icosahedron 2196:truncated tetrahedron 2009:non-convex polyhedron 1563:Truncated icosahedron 1282: 1243: 1203: 1163:Cartesian coordinates 1152: 1145:Cartesian coordinates 1033:Pyritohedral symmetry 1008:snub tetratetrahedron 846: 710:Pyritohedral symmetry 370: 321: 242:equilateral triangles 217:) or "icosahedrons". 46: 35: 2285:rhombic dodecahedron 2211:truncated octahedron 1210:Jessen's icosahedron 1204:Jessen's icosahedron 1196:Jessen's icosahedron 1167:truncated octahedron 1155:truncated octahedron 1139:icosahedral symmetry 1037:Tetrahedral symmetry 1023:truncated octahedron 916:, , (332), order 12 900:, , (3*2), order 24 809: 701:icosahedral symmetry 510:(Convex) icosahedron 445:Stellated icosahedra 351:regular dodecahedron 298:icosahedral symmetry 294:equilateral triangle 240:—whose faces are 20 2320:triakis icosahedron 2295:tetrakis hexahedron 2280:triakis tetrahedron 2216:rhombicuboctahedron 1339:(plus 2 ends = 20). 1332:(plus 1 base = 20). 1302:rhombic icosahedron 1296:Rhombic icosahedron 1290:Rhombic icosahedron 1284:Rhombic icosahedron 1108:regular icosahedron 1041:isosceles triangles 996:regular icosahedron 332:regular icosahedron 322:Three interlocking 314:Regular icosahedron 270:regular icosahedron 234:regular icosahedron 38:regular icosahedron 2513:Geodesic polyhedra 2290:triakis octahedron 2175:Archimedean solids 1950:regular polyhedron 1944:uniform polyhedron 1906:Hectotriadiohedron 1287: 1254: 1230:scissors congruent 1206: 1173:vertices deleted. 1159: 1016:pseudo-icosahedron 841: 835: 490:Uniform duals 380: 328: 248:Regular icosahedra 53: 41: 2518:Individual graphs 2500: 2499: 2419: 2418: 2256:snub dodecahedron 2231:icosidodecahedron 2086: 2085: 1987:Archimedean solid 1974:convex polyhedron 1882:Icosidodecahedron 1554: 1553: 1250:pseudoicosahedron 992: 991: 988: 987: 707: 706: 545:Great icosahedron 495:Regular compounds 384:great icosahedron 363:Great icosahedron 357:Great icosahedron 324:golden rectangles 302:great icosahedron 284:Great icosahedron 16:(Redirected from 2525: 2378: 2374:Dihedral uniform 2349:Dihedral regular 2272: 2188: 2137: 2113: 2106: 2099: 2090: 1922:elemental things 1900:Enneacontahedron 1870:Icositetrahedron 1720: 1713: 1706: 1697: 1690: 1684: 1678: 1677: 1667: 1661: 1660: 1652: 1643: 1642: 1640: 1616: 1610: 1609: 1589: 1506: 1499: 1492: 1485: 1478: 1471: 1458: 1447: 1436: 1425: 1414: 1403: 1376: 1373:are icosahedra: 1275:Other icosahedra 1178:snub tetrahedron 1136: 1135: 1134: 1130: 1129: 1125: 1124: 1120: 1119: 1115: 1114: 1105: 1104: 1103: 1099: 1098: 1094: 1093: 1089: 1088: 1084: 1083: 1077: 1076: 1075: 1071: 1070: 1066: 1065: 1061: 1060: 1056: 1055: 1048:Coxeter diagrams 1012:snub tetrahedron 971: 964: 957: 947: 850: 848: 847: 842: 840: 839: 793: 787: 786: 785: 781: 780: 776: 775: 771: 770: 766: 765: 759: 753: 752: 751: 747: 746: 742: 741: 737: 736: 732: 731: 723:Coxeter diagrams 714: 686: 679: 672: 665: 658: 651: 644: 637: 630: 621: 614: 607: 600: 593: 586: 579: 572: 565: 555:Final stellation 471: 440: 438: 437: 434: 431: 409: 407: 406: 403: 400: 280: 265: 216: 215: 212: 211: 208: 205: 174: 173: 170: 169: 166: 163: 160: 157: 154: 151: 148: 145: 142: 139: 136: 127: 126: 123: 122: 119: 114: 113: 110: 105: 104: 101: 98: 95: 92: 89: 86: 83: 80: 77: 74: 71: 21: 2533: 2532: 2528: 2527: 2526: 2524: 2523: 2522: 2503: 2502: 2501: 2496: 2485: 2424:Dihedral others 2415: 2394: 2369: 2344: 2273: 2270: 2269: 2260: 2189: 2178: 2177: 2168: 2131: 2129:Platonic solids 2123: 2117: 2087: 2082: 2033: 2022:Star polyhedron 2004: 1969: 1917: 1894:Hexecontahedron 1876:Triacontahedron 1858: 1849:Enneadecahedron 1839:Heptadecahedron 1829:Pentadecahedron 1824:Tetradecahedron 1797: 1736: 1729: 1724: 1694: 1693: 1685: 1681: 1669: 1668: 1664: 1654: 1653: 1646: 1618: 1617: 1613: 1607: 1591: 1590: 1586: 1581: 1559: 1549: 1547: 1545: 1540: 1538: 1533: 1531: 1526: 1521: 1516: 1514: 1512: 1459: 1448: 1437: 1426: 1415: 1404: 1367: 1322: 1314:face-transitive 1298: 1292: 1277: 1260: 1238: 1223:dihedral angles 1212: 1198: 1184:, 1, 0), where 1147: 1132: 1127: 1122: 1117: 1112: 1110: 1101: 1096: 1091: 1086: 1081: 1079: 1073: 1068: 1063: 1058: 1053: 1051: 1004:snub octahedron 948: 922:Dual polyhedron 914: 898: 863: 861: 834: 833: 827: 826: 816: 807: 806: 804: 799:Schläfli symbol 783: 778: 773: 768: 763: 761: 760: 754:(pyritohedral) 749: 744: 739: 734: 729: 727: 712: 447: 435: 432: 429: 428: 426: 419:dual polyhedron 404: 401: 398: 397: 395: 392:Schläfli symbol 365: 359: 347:dual polyhedron 340:Schläfli symbol 336:Platonic solids 316: 310: 290: 289: 288: 287: 286: 281: 273: 272: 266: 257: 256: 250: 238:Platonic solids 202: 198: 133: 129: 116: 107: 68: 64: 30: 23: 22: 15: 12: 11: 5: 2531: 2529: 2521: 2520: 2515: 2505: 2504: 2498: 2497: 2490: 2487: 2486: 2484: 2483: 2478: 2473: 2468: 2463: 2458: 2453: 2448: 2443: 2438: 2433: 2427: 2425: 2421: 2420: 2417: 2416: 2414: 2413: 2408: 2402: 2400: 2396: 2395: 2393: 2392: 2387: 2381: 2375: 2371: 2370: 2368: 2367: 2360: 2352: 2350: 2346: 2345: 2343: 2342: 2337: 2332: 2327: 2322: 2317: 2312: 2307: 2302: 2297: 2292: 2287: 2282: 2276: 2274: 2267:Catalan solids 2265: 2262: 2261: 2259: 2258: 2253: 2248: 2243: 2238: 2233: 2228: 2223: 2218: 2213: 2208: 2206:truncated cube 2203: 2198: 2192: 2190: 2173: 2170: 2169: 2167: 2166: 2161: 2156: 2151: 2146: 2140: 2138: 2125: 2124: 2118: 2116: 2115: 2108: 2101: 2093: 2084: 2083: 2081: 2080: 2078:parallelepiped 2075: 2070: 2065: 2060: 2055: 2050: 2044: 2042: 2035: 2034: 2032: 2031: 2025: 2019: 2012: 2010: 2006: 2005: 2003: 2002: 1996: 1990: 1984: 1981:Platonic solid 1977: 1975: 1971: 1970: 1968: 1967: 1966: 1965: 1959: 1953: 1941: 1936: 1931: 1925: 1923: 1919: 1918: 1916: 1915: 1909: 1903: 1897: 1891: 1885: 1879: 1873: 1866: 1864: 1860: 1859: 1857: 1856: 1851: 1846: 1844:Octadecahedron 1841: 1836: 1834:Hexadecahedron 1831: 1826: 1821: 1816: 1811: 1805: 1803: 1799: 1798: 1796: 1795: 1790: 1785: 1780: 1775: 1770: 1765: 1760: 1755: 1750: 1744: 1742: 1738: 1737: 1734: 1731: 1730: 1725: 1723: 1722: 1715: 1708: 1700: 1692: 1691: 1679: 1662: 1644: 1611: 1605: 1583: 1582: 1580: 1577: 1576: 1575: 1570: 1565: 1558: 1555: 1552: 1551: 1542: 1535: 1528: 1523: 1518: 1508: 1507: 1500: 1493: 1486: 1479: 1472: 1464: 1463: 1452: 1441: 1430: 1419: 1408: 1396: 1395: 1392: 1389: 1386: 1383: 1380: 1371:Johnson solids 1366: 1365:Johnson solids 1363: 1362: 1361: 1354: 1347: 1340: 1333: 1321: 1318: 1294:Main article: 1291: 1288: 1276: 1273: 1256:Main article: 1237: 1234: 1208:Main article: 1197: 1194: 1146: 1143: 1141:of order 120. 990: 989: 986: 985: 973: 972: 965: 953: 952: 940: 939: 934: 930: 929: 924: 918: 917: 912: 908: 906:Rotation group 902: 901: 896: 892: 890:Symmetry group 886: 885: 882: 876: 875: 872: 866: 865: 858: 852: 851: 838: 832: 829: 828: 825: 822: 821: 819: 814: 801: 795: 794: 788:(tetrahedral) 725: 719: 718: 711: 708: 705: 704: 688: 687: 680: 673: 666: 659: 652: 645: 638: 631: 623: 622: 615: 608: 601: 594: 587: 580: 573: 566: 558: 557: 552: 547: 542: 537: 532: 527: 522: 517: 512: 506: 505: 502: 497: 492: 487: 481: 480: 456:In their book 446: 443: 361:Main article: 358: 355: 312:Main article: 309: 306: 282: 275: 274: 267: 260: 259: 258: 254: 253: 252: 251: 249: 246: 28: 24: 14: 13: 10: 9: 6: 4: 3: 2: 2530: 2519: 2516: 2514: 2511: 2510: 2508: 2494: 2488: 2482: 2479: 2477: 2474: 2472: 2469: 2467: 2464: 2462: 2459: 2457: 2454: 2452: 2449: 2447: 2444: 2442: 2439: 2437: 2434: 2432: 2429: 2428: 2426: 2422: 2412: 2409: 2407: 2404: 2403: 2401: 2397: 2391: 2388: 2386: 2383: 2382: 2379: 2376: 2372: 2366: 2365: 2361: 2359: 2358: 2354: 2353: 2351: 2347: 2341: 2338: 2336: 2333: 2331: 2328: 2326: 2323: 2321: 2318: 2316: 2313: 2311: 2308: 2306: 2303: 2301: 2298: 2296: 2293: 2291: 2288: 2286: 2283: 2281: 2278: 2277: 2275: 2268: 2263: 2257: 2254: 2252: 2249: 2247: 2244: 2242: 2239: 2237: 2234: 2232: 2229: 2227: 2224: 2222: 2219: 2217: 2214: 2212: 2209: 2207: 2204: 2202: 2201:cuboctahedron 2199: 2197: 2194: 2193: 2191: 2186: 2182: 2176: 2171: 2165: 2162: 2160: 2157: 2155: 2152: 2150: 2147: 2145: 2142: 2141: 2139: 2135: 2130: 2126: 2122: 2114: 2109: 2107: 2102: 2100: 2095: 2094: 2091: 2079: 2076: 2074: 2071: 2069: 2066: 2064: 2061: 2059: 2056: 2054: 2051: 2049: 2046: 2045: 2043: 2040: 2036: 2029: 2026: 2023: 2020: 2017: 2014: 2013: 2011: 2007: 2000: 1999:Johnson solid 1997: 1994: 1993:Catalan solid 1991: 1988: 1985: 1982: 1979: 1978: 1976: 1972: 1963: 1960: 1957: 1954: 1951: 1948: 1947: 1945: 1942: 1940: 1937: 1935: 1932: 1930: 1927: 1926: 1924: 1920: 1913: 1910: 1907: 1904: 1901: 1898: 1895: 1892: 1889: 1888:Hexoctahedron 1886: 1883: 1880: 1877: 1874: 1871: 1868: 1867: 1865: 1861: 1855: 1852: 1850: 1847: 1845: 1842: 1840: 1837: 1835: 1832: 1830: 1827: 1825: 1822: 1820: 1819:Tridecahedron 1817: 1815: 1812: 1810: 1809:Hendecahedron 1807: 1806: 1804: 1800: 1794: 1791: 1789: 1786: 1784: 1781: 1779: 1776: 1774: 1771: 1769: 1766: 1764: 1761: 1759: 1756: 1754: 1751: 1749: 1746: 1745: 1743: 1739: 1732: 1728: 1721: 1716: 1714: 1709: 1707: 1702: 1701: 1698: 1689:on Mathworld. 1688: 1683: 1680: 1675: 1674: 1666: 1663: 1658: 1657:"Fool's Gold" 1651: 1649: 1645: 1639: 1634: 1630: 1626: 1622: 1615: 1612: 1608: 1606:3-12-539683-2 1602: 1598: 1594: 1593:Jones, Daniel 1588: 1585: 1578: 1574: 1571: 1569: 1566: 1564: 1561: 1560: 1556: 1543: 1541:10 pentagons 1536: 1534:10 pentagons 1529: 1524: 1519: 1510: 1505: 1501: 1498: 1494: 1491: 1487: 1484: 1480: 1477: 1473: 1470: 1466: 1465: 1462: 1457: 1453: 1451: 1446: 1442: 1440: 1435: 1431: 1429: 1424: 1420: 1418: 1413: 1409: 1407: 1402: 1398: 1393: 1390: 1387: 1384: 1381: 1378: 1377: 1374: 1372: 1364: 1359: 1358:trapezohedron 1355: 1352: 1348: 1345: 1341: 1338: 1334: 1331: 1327: 1326: 1325: 1319: 1317: 1315: 1311: 1307: 1303: 1297: 1289: 1285: 1281: 1274: 1272: 1270: 1265: 1264:cuboctahedron 1259: 1251: 1247: 1242: 1236:Cuboctahedron 1235: 1233: 1231: 1226: 1224: 1221: 1217: 1211: 1202: 1193: 1191: 1187: 1183: 1179: 1174: 1172: 1168: 1164: 1156: 1151: 1144: 1142: 1140: 1109: 1049: 1044: 1042: 1038: 1034: 1030: 1028: 1024: 1021: 1017: 1013: 1009: 1005: 1001: 997: 983: 979: 978:cuboctahedron 974: 970: 966: 963: 959: 958: 954: 951: 946: 941: 938: 935: 931: 928: 925: 923: 919: 915: 909: 907: 903: 899: 893: 891: 887: 883: 881: 877: 873: 871: 867: 864:12 isosceles 862:8 equilateral 860:20 triangles: 859: 857: 853: 836: 830: 823: 817: 812: 802: 800: 796: 792: 758: 726: 724: 720: 715: 709: 702: 698: 694: 689: 685: 681: 678: 674: 671: 667: 664: 660: 657: 653: 650: 646: 643: 636: 632: 629: 625: 624: 620: 616: 613: 609: 606: 602: 599: 595: 592: 588: 585: 581: 578: 571: 567: 564: 560: 559: 556: 553: 551: 548: 546: 543: 541: 538: 536: 533: 531: 528: 526: 523: 521: 518: 516: 513: 511: 508: 507: 501: 498: 496: 491: 486: 483: 482: 479: 478: 472: 469: 466: 463: 461: 460: 454: 451: 444: 442: 424: 420: 415: 413: 393: 389: 385: 378: 374: 369: 364: 356: 354: 352: 348: 343: 341: 337: 333: 325: 320: 315: 307: 305: 303: 299: 295: 285: 279: 271: 264: 247: 245: 243: 239: 235: 231: 227: 223: 218: 214: 196: 192: 189: 185: 182: 181:Ancient Greek 178: 172: 125: 62: 58: 50: 45: 39: 34: 27: 19: 2492: 2411:trapezohedra 2362: 2355: 2159:dodecahedron 1912:Apeirohedron 1863:>20 faces 1853: 1814:Dodecahedron 1682: 1672: 1665: 1628: 1624: 1614: 1596: 1587: 1544:13 triangles 1537:10 triangles 1530:10 triangles 1511:16 triangles 1368: 1323: 1299: 1269:double cover 1261: 1227: 1215: 1213: 1190:golden ratio 1185: 1181: 1177: 1175: 1160: 1045: 1031: 1015: 1011: 1007: 1003: 1000:pyritohedral 995: 993: 927:Pyritohedron 500:Regular star 474: 467: 464: 457: 455: 448: 416: 381: 375:monument in 371:A detail of 344: 331: 329: 301: 291: 236:—one of the 219: 194: 191: 187: 184: 60: 54: 26: 2181:semiregular 2164:icosahedron 2144:tetrahedron 1854:Icosahedron 1802:11–20 faces 1788:Enneahedron 1778:Heptahedron 1768:Pentahedron 1763:Tetrahedron 1687:Icosahedron 1548:3 pentagons 1527:12 squares 1525:8 triangles 1522:12 squares 1520:8 triangles 1137:, (*532), 1027:equilateral 805:sr{3,3} or 61:icosahedron 51:icosahedron 18:Icosahedral 2507:Categories 2476:prismatoid 2406:bipyramids 2390:antiprisms 2364:hosohedron 2154:octahedron 2039:prismatoid 2024:(infinite) 1793:Decahedron 1783:Octahedron 1773:Hexahedron 1748:Monohedron 1741:1–10 faces 1631:(2): 139. 1579:References 1550:1 hexagon 1517:1 hexagon 1306:zonohedron 1246:octahedron 1171:alternated 1020:alternated 933:Properties 450:Stellation 177:polyhedron 49:tensegrity 2471:birotunda 2461:bifrustum 2226:snub cube 2121:polyhedra 2053:antiprism 1758:Trihedron 1727:Polyhedra 1546:3 squares 1513:3 squares 1356:10-sided 1351:bipyramid 1349:10-sided 1344:antiprism 1335:18-sided 1328:19-sided 697:compounds 693:polyhedra 412:pentagram 377:Amsterdam 230:stellated 2451:bicupola 2431:pyramids 2357:dihedron 1753:Dihedron 1568:600-cell 1557:See also 1369:Several 1342:9-sided 880:Vertices 475:Notable 188:(eíkosi) 57:geometry 2493:italics 2481:scutoid 2466:rotunda 2456:frustum 2185:uniform 2134:regular 2119:Convex 2073:pyramid 2058:frustum 1573:Icosoku 1330:pyramid 1188:is the 504:Others 485:Regular 439:⁠ 427:⁠ 421:is the 408:⁠ 396:⁠ 394:is {3, 373:Spinoza 349:is the 268:Convex 222:similar 195:(hédra) 175:) is a 36:Convex 2446:cupola 2399:duals: 2385:prisms 2063:cupola 1939:vertex 1603:  1539:  1532:  1515:  1228:It is 1014:, and 937:convex 803:s{3,4} 390:. Its 228:, non- 226:convex 186:εἴκοσι 2068:wedge 2048:prism 1908:(132) 1337:prism 1304:is a 1220:right 1169:with 870:Edges 856:Faces 699:with 183: 59:, an 2149:cube 2030:(57) 2001:(92) 1995:(13) 1989:(13) 1958:(16) 1934:edge 1929:face 1902:(90) 1896:(60) 1890:(48) 1884:(32) 1878:(30) 1872:(24) 1601:ISBN 1394:J92 1391:J60 1388:J59 1385:J36 1382:J35 1379:J22 1300:The 1161:The 1078:and 695:and 417:Its 382:The 345:Its 193:ἕδρα 2183:or 2018:(4) 1983:(5) 1952:(9) 1914:(∞) 1633:doi 950:Net 884:12 128:or 115:-,- 55:In 2509:: 2041:‌s 1647:^ 1629:21 1627:. 1623:. 1316:. 1248:, 1225:. 1192:. 1050:: 1043:. 1010:, 1006:, 994:A 984:. 703:. 304:. 244:. 232:) 201:/- 168:ən 159:iː 135:aɪ 124:-/ 121:oʊ 106:,- 103:ən 94:iː 73:aɪ 47:A 2495:. 2187:) 2179:( 2136:) 2132:( 2112:e 2105:t 2098:v 1719:e 1712:t 1705:v 1659:. 1641:. 1635:: 1186:ϕ 1182:ϕ 913:d 911:T 897:h 895:T 837:} 831:3 824:3 818:{ 813:s 436:2 433:/ 430:5 425:{ 405:2 402:/ 399:5 213:/ 210:ə 207:r 204:d 171:/ 165:r 162:d 156:h 153:ˈ 150:ə 147:s 144:ɒ 141:k 138:ˌ 132:/ 118:k 112:ə 109:k 100:r 97:d 91:h 88:ˈ 85:ə 82:s 79:ɒ 76:k 70:ˌ 67:/ 63:( 20:)

Index

Icosahedral

regular icosahedron

tensegrity
geometry
/ˌkɒsəˈhdrən,-kə-,-k-/
/ˌkɒsəˈhdrən/
polyhedron
Ancient Greek
/-drə/
similar
convex
stellated
regular icosahedron
Platonic solids
equilateral triangles

regular icosahedron

Great icosahedron
equilateral triangle
icosahedral symmetry
Regular icosahedron

golden rectangles
Platonic solids
Schläfli symbol
dual polyhedron
regular dodecahedron

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