14-simplex

14-simplex
Rank	14
Type	Regular
Notation
Coxeter diagram	x3o3o3o3o3o3o3o3o3o3o3o3o3o ()
Schläfli symbol	{3,3,3,3,3,3,3,3,3,3,3,3,3}
Elements
Tradaka	15 13-simplices
Doka	105 12-simplices
Henda	455 11-simplices
Daka	1365 10-simplices
Xenna	3003 9-simplices
Yotta	5005 8-simplices
Zetta	6435 7-simplices
Exa	6435 6-simplices
Peta	5005 hexatera
Tera	3003 pentachora
Cells	1365 tetrahedra
Faces	455 triangles
Edges	105
Vertices	15
Vertex figure	13-simplex, edge length 1
Measures (edge length 1)
Circumradius	${\frac {\sqrt {105}}{15}}\approx 0.68313$
Inradius	${\frac {\sqrt {105}}{210}}\approx 0.048795$
Hypervolume	${\frac {\sqrt {15}}{11158821273600}}\approx 3.4708\times 10^{-13}$
Dihedral angle	$\arccos \left({\frac {1}{14}}\right)\approx 85.90396^{\circ }$
Height	${\frac {\sqrt {105}}{14}}\approx 0.73193$
Central density	1
Number of external pieces	15
Level of complexity	1
Related polytopes
Army	14-simplex
Regiment	14-simplex
Dual	14-simplex
Conjugate	None
Abstract & topological properties
Flag count	1307674368000
Euler characteristic	0
Orientable	Yes
Properties
Symmetry	A14, order 1307674368000
Flag orbits	1
Convex	Yes
Nature	Tame

The 14-simplex (also called the pentadecatradakon) is the simplest possible non-degenerate 14-polytope. The full symmetry version has 15 regular 13-simplices as facets, joining 3 to a facet and 14 to a vertex, and is regular.

Vertex coordinates

The vertices of a regular 14-simplex of edge length 1, centered at the origin, are given by:

• $\left(\pm {\frac {1}{2}},\,-{\frac {\sqrt {3}}{6}},\,-{\frac {\sqrt {6}}{12}},\,-{\frac {\sqrt {10}}{20}},\,-{\frac {\sqrt {15}}{30}},\,-{\frac {\sqrt {21}}{42}},\,-{\frac {\sqrt {7}}{28}},\,-{\frac {1}{12}},\,-{\frac {\sqrt {5}}{30}},\,-{\frac {\sqrt {55}}{110}},\,-{\frac {\sqrt {66}}{132}},\,-{\frac {\sqrt {78}}{156}},\,-{\frac {\sqrt {91}}{182}},\,-{\frac {\sqrt {105}}{210}}\right)$,
• $\left(0,\,{\frac {\sqrt {3}}{3}},\,-{\frac {\sqrt {6}}{12}},\,-{\frac {\sqrt {10}}{20}},\,-{\frac {\sqrt {15}}{30}},\,-{\frac {\sqrt {21}}{42}},\,-{\frac {\sqrt {7}}{28}},\,-{\frac {1}{12}},\,-{\frac {\sqrt {5}}{30}},\,-{\frac {\sqrt {55}}{110}},\,-{\frac {\sqrt {66}}{132}},\,-{\frac {\sqrt {78}}{156}},\,-{\frac {\sqrt {91}}{182}},\,-{\frac {\sqrt {105}}{210}}\right)$,
• $\left(0,\,0,\,{\frac {\sqrt {6}}{4}},\,-{\frac {\sqrt {10}}{20}},\,-{\frac {\sqrt {15}}{30}},\,-{\frac {\sqrt {21}}{42}},\,-{\frac {\sqrt {7}}{28}},\,-{\frac {1}{12}},\,-{\frac {\sqrt {5}}{30}},\,-{\frac {\sqrt {55}}{110}},\,-{\frac {\sqrt {66}}{132}},\,-{\frac {\sqrt {78}}{156}},\,-{\frac {\sqrt {91}}{182}},\,-{\frac {\sqrt {105}}{210}}\right)$,
• $\left(0,\,0,\,0,\,{\frac {\sqrt {10}}{5}},\,-{\frac {\sqrt {15}}{30}},\,-{\frac {\sqrt {21}}{42}},\,-{\frac {\sqrt {7}}{28}},\,-{\frac {1}{12}},\,-{\frac {\sqrt {5}}{30}},\,-{\frac {\sqrt {55}}{110}},\,-{\frac {\sqrt {66}}{132}},\,-{\frac {\sqrt {78}}{156}},\,-{\frac {\sqrt {91}}{182}},\,-{\frac {\sqrt {105}}{210}}\right)$,
• $\left(0,\,0,\,0,\,0,\,{\frac {\sqrt {15}}{6}},\,-{\frac {\sqrt {21}}{42}},\,-{\frac {\sqrt {7}}{28}},\,-{\frac {1}{12}},\,-{\frac {\sqrt {5}}{30}},\,-{\frac {\sqrt {55}}{110}},\,-{\frac {\sqrt {66}}{132}},\,-{\frac {\sqrt {78}}{156}},\,-{\frac {\sqrt {91}}{182}},\,-{\frac {\sqrt {105}}{210}}\right)$,
• $\left(0,\,0,\,0,\,0,\,0,\,{\frac {\sqrt {21}}{7}},\,-{\frac {\sqrt {7}}{28}},\,-{\frac {1}{12}},\,-{\frac {\sqrt {5}}{30}},\,-{\frac {\sqrt {55}}{110}},\,-{\frac {\sqrt {66}}{132}},\,-{\frac {\sqrt {78}}{156}},\,-{\frac {\sqrt {91}}{182}},\,-{\frac {\sqrt {105}}{210}}\right)$,
• $\left(0,\,0,\,0,\,0,\,0,\,0,\,{\frac {\sqrt {7}}{4}},\,-{\frac {1}{12}},\,-{\frac {\sqrt {5}}{30}},\,-{\frac {\sqrt {55}}{110}},\,-{\frac {\sqrt {66}}{132}},\,-{\frac {\sqrt {78}}{156}},\,-{\frac {\sqrt {91}}{182}},\,-{\frac {\sqrt {105}}{210}}\right)$,
• $\left(0,\,0,\,0,\,0,\,0,\,0,\,0,\,{\frac {2}{3}},\,-{\frac {\sqrt {5}}{30}},\,-{\frac {\sqrt {55}}{110}},\,-{\frac {\sqrt {66}}{132}},\,-{\frac {\sqrt {78}}{156}},\,-{\frac {\sqrt {91}}{182}},\,-{\frac {\sqrt {105}}{210}}\right)$,
• $\left(0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,{\frac {3{\sqrt {5}}}{10}},\,-{\frac {\sqrt {55}}{110}},\,-{\frac {\sqrt {66}}{132}},\,-{\frac {\sqrt {78}}{156}},\,-{\frac {\sqrt {91}}{182}},\,-{\frac {\sqrt {105}}{210}}\right)$,
• $\left(0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,{\frac {\sqrt {55}}{11}},\,-{\frac {\sqrt {66}}{132}},\,-{\frac {\sqrt {78}}{156}},\,-{\frac {\sqrt {91}}{182}},\,-{\frac {\sqrt {105}}{210}}\right)$,
• $\left(0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,{\frac {\sqrt {66}}{12}},\,-{\frac {\sqrt {78}}{156}},\,-{\frac {\sqrt {91}}{182}},\,-{\frac {\sqrt {105}}{210}}\right)$,
• $\left(0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,{\frac {\sqrt {78}}{13}},\,-{\frac {\sqrt {91}}{182}},\,-{\frac {\sqrt {105}}{210}}\right)$,
• $\left(0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,{\frac {\sqrt {91}}{14}},\,-{\frac {\sqrt {105}}{210}}\right)$,
• $\left(0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,{\frac {\sqrt {105}}{15}}\right)$.

Much simpler coordinates can be given in 15 dimensions, as all permutations of:

• $\left({\frac {\sqrt {2}}{2}},\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,0,\,0\right)$.