Acronym	starp (old: restap)
TOCID symbol	(5/3)Q
Name	tristrophic pentagrammic antiprism, stellar retroprism (retrograde stellar antiprism), 5/3-antiprism
	© ©
Circumradius	sqrt[(5-sqrt(5))/8] = 0.587785
Vertex figure	[33,5/3]
General of army	pap
Colonel of regiment	(itself, evon so not being locally convex)
Face vector	10, 20, 12
Confer	more general: nd-ap   uniform relative: gike   compounds: gissed   gidasid   general polytopal classes: segmentohedra
External links

Like pap can be seen as (parallel) bi-diminished ike, starp can be seen as (parallel) bi-diminished gike. The locally convex cover of the latter is sissid. But as 2 opposit peaks are missing, from the 5 pentagrammal edges of each face only 3 remain in this edge skeleton (except for the 2 bases), especially they do not close, thus this figure has no locally convex cover and will be considered its own colonel.

This polyhedron is an edge-faceting of the small stellated dodecahedron (sissid).

Incidence matrix according to Dynkin symbol

s2s5/3s

demi( . .   . ) | 10 | 1 1  2 | 1  3
----------------+----+--------+-----
      s2s   .   |  2 | 5 *  * | 0  2
      s 2   s   |  2 | * 5  * | 0  2
sefa( . s5/3s ) |  2 | * * 10 | 1  1
----------------+----+--------+-----
      . s5/3s   ♦  5 | 0 0  5 | 2  *
sefa( s2s5/3s ) |  3 | 1 1  1 | * 10

starting figure: x x5/3x

xo5/3ox&#x   → height = sqrt[(5-sqrt(5))/10] = 0.525731
({5/3} || dual {5/3})

o.5/3o.    | 5 * | 2  2 0 | 1 2 1 0
.o5/3.o    | * 5 | 0  2 2 | 0 1 2 1
-----------+-----+--------+--------
x.   ..    | 2 0 | 5  * * | 1 1 0 0
oo5/3oo&#x | 1 1 | * 10 * | 0 1 1 0
..   .x    | 0 2 | *  * 5 | 0 0 1 1
-----------+-----+--------+--------
x.5/3o.    | 5 0 | 5  0 0 | 1 * * *
xo   ..&#x | 2 1 | 1  2 0 | * 5 * *
..   ox&#x | 1 2 | 0  2 1 | * * 5 *
.o5/3.x    | 0 5 | 0  0 5 | * * * 1