Knowledge (XXG)

Octahedral pyramid

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with octahedral bounding cells, surrounding a central vertex with 24 edge-length long radii. The 4-dimensional content of a unit-edge-length 24-cell is 2, so the content of the regular octahedral pyramid is 1/12. The 24-cell tessellates 4-dimensional space as the
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with four tetrahedra wrapped around the common edge. If the height of the two apexes are the same, it can be given a higher symmetry name ∨ {4} = { } ∨ {4}, joining an edge to a perpendicular square.
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passing through the center of the 16-cell. Therefore placing two regular octahedral pyramids base to base constructs a 16-cell. The 16-cell tessellates 4-dimensional space as the
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which meet at the apex. Since an octahedron has a circumradius divided by edge length less than one, the triangular pyramids can be made with regular faces (as regular
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Exactly 24 regular octahedral pyramids will fit together around a vertex in four-dimensional space (the apex of each pyramid). This construction yields a
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along with another one more square pyramid meeting at the apex. It can also be seen in an edge-centered projection as a
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Example 4-dimensional coordinates, 6 points in first 3 coordinates for cube and 4th dimension for the apex.
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Example 4-dimensional coordinates, 8 points in first 3 coordinates for cube and 4th dimension for the apex.
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Example 4-dimensional coordinates, 2 coordinates for square, and axial points for pyramidal points.
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The graph of the octahedral pyramid is the only possible minimal counterexample to
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exists as a vertex figure in uniform polytopes of the form
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Axial-Symmetrical Edge Facetings of Uniform Polyhedra
545:, ( ) ∨ , is a bisected octahedral pyramid. It has a 698:"20 years of Negami's planar cover conjecture" 860: 8: 400: 29: 867: 853: 718: 682:"3D convex uniform polyhedra x3o4o - oct" 572:, { } ∨ , or other lower symmetry forms. 209:. Two copies can be augmented to make an 405: 358:The dual to the octahedral pyramid is a 34: 672: 202:) by computing the appropriate height. 217:Occurrences of the octahedral pyramid 7: 821: 819: 839:. You can help Knowledge (XXG) by 328:are themselves projective-planar. 205:Having all regular cells, it is a 25: 633:bitruncated tesseractic honeycomb 324:, that the connected graphs with 823: 644: 639: 621: 616: 611: 606: 601: 596: 591: 586: 581: 466: 456: 411: 406: 374: 312: 302: 297: 292: 287: 282: 277: 272: 267: 262: 213:which is also a Blind polytope. 96: 86: 35: 528: 514: 506: 498: 490: 474: 445: 429: 419: 163: 141: 131: 123: 115: 104: 75: 57: 47: 252:The octahedral pyramid is the 229:around every vertex, with the 1: 566:rectangular-pyramidal pyramid 362:, seen as a cubic base and 6 759:"Segmentotope squasc, K-4.4" 804:"Segmentotope octpy, K-4.3" 912: 818: 729:10.1007/s00373-010-0934-9 570:rhombic-pyramidal pyramid 531: 519: 509: 501: 493: 477: 434: 422: 401:Square-pyramidal pyramid 166: 146: 134: 126: 118: 107: 62: 50: 706:Graphs and Combinatorics 577:square-pyramidal pyramid 564:can be distorted into a 562:square-pyramidal pyramid 543:square-pyramidal pyramid 394:Square-pyramidal pyramid 18:Square-pyramidal pyramid 782:Glossary for Hyperspace 629:bitruncated 5-orthoplex 696:Hliněný, Petr (2010), 258:truncated 5-orthoplex 686:1/sqrt(2) = 0.707107 211:octahedral bipyramid 891:Pyramids (geometry) 802:Klitzing, Richard. 793:Klitzing, Richard. 788:on 4 February 2007. 776:Olshevsky, George. 757:Klitzing, Richard. 680:Klitzing, Richard. 322:Negami's conjecture 227:octahedral pyramids 30:Octahedral pyramid 812:Richard Klitzing, 795:"4D Segmentotopes" 424:Polyhedral pyramid 193:triangular pyramid 191:on the base and 8 187:is bounded by one 185:octahedral pyramid 52:Polyhedral pyramid 848: 847: 539: 538: 437:∨ {4} = { } ∨ {4} 247:24-cell honeycomb 235:16-cell honeycomb 179:In 4-dimensional 177: 176: 170:, regular-cells, 16:(Redirected from 903: 869: 862: 855: 827: 820: 807: 798: 789: 784:. Archived from 763: 762: 754: 748: 747: 722: 702: 693: 687: 685: 677: 648: 643: 627:, including the 626: 625: 624: 620: 619: 615: 614: 610: 609: 605: 604: 600: 599: 595: 594: 590: 589: 585: 584: 555:square bipyramid 535:, regular-faced 470: 460: 415: 410: 398: 378: 316: 307: 306: 305: 301: 300: 296: 295: 291: 290: 286: 285: 281: 280: 276: 275: 271: 270: 266: 265: 100: 90: 42:Schlegel diagram 39: 27: 21: 911: 910: 906: 905: 904: 902: 901: 900: 876: 875: 874: 873: 801: 792: 775: 772: 767: 766: 756: 755: 751: 720:10.1.1.605.4932 700: 695: 694: 690: 679: 678: 674: 669: 622: 617: 612: 607: 602: 597: 592: 587: 582: 580: 523: 521: 482: 461: 440: 438: 436: 431:Schläfli symbol 396: 364:square pyramids 356: 351: 349:Other polytopes 303: 298: 293: 288: 283: 278: 273: 268: 263: 261: 219: 158: 156: 154: 152: 150: 91: 70: 68: 66: 64: 59:Schläfli symbol 40: 23: 22: 15: 12: 11: 5: 909: 907: 899: 898: 896:Geometry stubs 893: 888: 878: 877: 872: 871: 864: 857: 849: 846: 845: 828: 817: 816: 810: 809: 808: 790: 771: 770:External links 768: 765: 764: 749: 713:(4): 525–536, 688: 671: 670: 668: 665: 664: 663: 660: 657: 650: 649: 568:, { } ∨ or a 547:square pyramid 537: 536: 530: 526: 525: 518: 516:Symmetry group 512: 511: 508: 504: 503: 500: 496: 495: 492: 488: 487: 476: 472: 471: 450: 447: 443: 442: 433: 427: 426: 421: 417: 416: 403: 402: 395: 392: 391: 390: 387: 380: 379: 366:meeting at an 355: 352: 350: 347: 346: 345: 342: 339: 336: 318: 317: 218: 215: 207:Blind polytope 175: 174: 172:Blind polytope 165: 161: 160: 148: 145: 143:Symmetry group 139: 138: 133: 129: 128: 125: 121: 120: 117: 113: 112: 106: 102: 101: 80: 77: 73: 72: 61: 55: 54: 49: 45: 44: 32: 31: 24: 14: 13: 10: 9: 6: 4: 3: 2: 908: 897: 894: 892: 889: 887: 884: 883: 881: 870: 865: 863: 858: 856: 851: 850: 844: 842: 838: 835:article is a 834: 829: 826: 822: 815: 811: 805: 800: 799: 796: 791: 787: 783: 779: 774: 773: 769: 760: 753: 750: 746: 742: 738: 734: 730: 726: 721: 716: 712: 708: 707: 699: 692: 689: 683: 676: 673: 666: 662:( 0, 0; 0; 1) 661: 659:( 0, 0; 1; 0) 658: 656:(±1,±1; 0; 0) 655: 654: 653: 647: 642: 638: 637: 636: 634: 630: 578: 573: 571: 567: 563: 558: 556: 552: 548: 544: 534: 527: 517: 513: 505: 497: 489: 486: 481: 473: 469: 465: 459: 455: 451: 448: 444: 432: 428: 425: 418: 414: 409: 404: 399: 393: 389:( 0, 0, 0; 1) 388: 386:(±1,±1,±1; 0) 385: 384: 383: 377: 373: 372: 371: 369: 365: 361: 360:cubic pyramid 354:Cubic pyramid 353: 348: 344:( 0, 0, 0; 1) 343: 341:( 0, 0,±1; 0) 340: 338:( 0,±1, 0; 0) 337: 335:(±1, 0, 0; 0) 334: 333: 332: 329: 327: 326:planar covers 323: 315: 311: 310: 309: 259: 255: 254:vertex figure 250: 248: 243: 238: 236: 232: 228: 224: 216: 214: 212: 208: 203: 201: 197: 194: 190: 186: 182: 173: 169: 162: 144: 140: 137: 136:Cubic pyramid 130: 122: 114: 111: 103: 99: 95: 89: 85: 81: 78: 74: 60: 56: 53: 46: 43: 38: 33: 28: 19: 841:expanding it 830: 786:the original 781: 752: 710: 704: 691: 675: 651: 576: 574: 569: 565: 561: 559: 551:tetrahedrons 549:base, and 4 542: 540: 464:( )∨{3} 454:( )∨{4} 381: 357: 330: 319: 251: 239: 226: 221:The regular 220: 204: 200:tetrahedrons 184: 178: 151:, , order 48 67:( ) ∨ s{2,6} 65:( ) ∨ r{3,3} 886:4-polytopes 529:Properties 164:Properties 63:( ) ∨ {3,4} 880:Categories 833:4-polytope 667:References 524:, order 8 522:, order 16 510:Self-dual 231:octahedron 189:octahedron 159:, order 8 157:, order 16 155:, order 12 153:, order 24 778:"Pyramid" 715:CiteSeerX 520:, order 8 499:Vertices 124:Vertices 94:( ) ∨ {3} 181:geometry 737:2669457 441:{ } ∨ 242:24-cell 223:16-cell 71:( ) ∨ 745:121645 743:  735:  717:  533:convex 491:Edges 475:Faces 446:Cells 439:{ } ∨ 435:( ) ∨ 256:for a 183:, the 168:convex 116:Edges 105:Faces 76:Cells 69:( ) ∨ 831:This 741:S2CID 701:(PDF) 507:Dual 420:Type 196:cells 132:Dual 84:{3,4} 48:Type 837:stub 631:and 575:The 560:The 541:The 368:apex 225:has 725:doi 494:13 485:{4} 480:{3} 478:12 119:18 110:{3} 108:20 882:: 780:. 739:, 733:MR 731:, 723:, 711:26 709:, 703:, 635:. 502:6 483:1 462:4 452:2 449:6 370:. 308:. 260:, 249:. 237:. 127:7 92:8 82:1 79:9 868:e 861:t 854:v 843:. 806:. 797:. 761:. 727:: 684:. 149:3 147:B 20:)

Index

Square-pyramidal pyramid

Schlegel diagram
Polyhedral pyramid
Schläfli symbol
{3,4}

( ) ∨ {3}

{3}
Cubic pyramid
Symmetry group
convex
Blind polytope
geometry
octahedron
triangular pyramid
cells
tetrahedrons
Blind polytope
octahedral bipyramid
16-cell
octahedron
16-cell honeycomb
24-cell
24-cell honeycomb
vertex figure
truncated 5-orthoplex

Negami's conjecture

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