Acronym hap, 6-ap Name hexagonal antiprism Circumradius sqrt[3+sqrt(3)]/2 = 1.087664 Vertex figure [33,6] General of army (is itself convex) Colonel of regiment (is itself locally convex) Dihedral angles between {3} and {3}:   arccos([1-2 sqrt(3)]/3) = 145.221891° between {3} and {6}:   arccos(1-2/sqrt(3)) = 98.899429° Confer more general: n-ap   general polytopal classes: segmentohedra Externallinks

Incidence matrix according to Dynkin symbol

```s2s6s

demi( . . .  ) | 12 | 1 1  2 | 1  3
---------------+----+--------+-----
s2s .    |  2 | 6 *  * | 0  2
s . s2*a |  2 | * 6  * | 0  2
sefa( . s6s  ) |  2 | * * 12 | 1  1
---------------+----+--------+-----
. s6s    ♦  6 | 0 0  6 | 2  *
sefa( s2s6s  ) |  3 | 1 1  1 | * 12

starting figure: x x6x
```

```s2s12o

demi( . .  . ) | 12 |  2  2 | 1  3
---------------+----+-------+-----
s2s  .   |  2 | 12  * | 0  2
sefa( . s12o ) |  2 |  * 12 | 1  1
---------------+----+-------+-----
. s12o   ♦  6 |  0  6 | 2  *
sefa( s2s12o ) |  3 |  2  1 | * 12

starting figure: x x12o
```

```xo6ox&#x   → height = sqrt[sqrt(3)-1] = 0.855600
({6} || dual {6})

o.6o.    | 6 * | 2  2 0 | 1 2 1 0
.o6.o    | * 6 | 0  2 2 | 0 1 2 1
---------+-----+--------+--------
x. ..    | 2 0 | 6  * * | 1 1 0 0
oo6oo&#x | 1 1 | * 12 * | 0 1 1 0
.. .x    | 0 2 | *  * 6 | 0 0 1 1
---------+-----+--------+--------
x.6o.    | 6 0 | 6  0 0 | 1 * * *
xo ..&#x | 2 1 | 1  2 0 | * 6 * *
.. ox&#x | 1 2 | 0  2 1 | * * 6 *
.o6.x    | 0 6 | 0  0 6 | * * * 1

snubbed forms: so6ox&#x
```