Acronym 2,n-dap
Name digon - n-gon duoantiprism,
hemiated square - 2n-gon duoprism
Circumradius sqrt[A2/2+B2/(4 sin2(π/2n))]
Especially s2s2s3s   s2s2s2s (hex)  
Confer
more general:
sns2sms  
general polytopal classes:
isogonal  
External
links
polytopewiki

These isogonal polychora are obtained by hemiation of the uniform 4,2n-duoprism (with n>2). But because of lower degree of freedom the three edge sizes A*sqrt(2), B*x(2n), sqrt(A2+B2) cannot be made all alike.

The exceptional case n=2 could be considered similarily, but the incidence matrices below will be different because of degeneracy. Then it becomes the hemiated tes (hex) and even happens to be regular.


Incidence matrix according to Dynkin symbol

s2s2sns (n>2)

demi( . . . . )   | 4N |  1  4  2 |  6  6 1 |  2  4 2
------------------+----+----------+---------+--------
      s2s . .     |  2 | 2N  *  * |  4  0 0 |  2  2 0  A*sqrt(2)
      . s2s .   & |  2 |  * 8N  * |  2  2 0 |  1  2 1  sqrt(A2+B2)
sefa( . . sns )   |  2 |  *  * 4N |  0  2 1 |  0  1 2  B*x(2n)
------------------+----+----------+---------+--------
sefa( s2s2s . ) & |  3 |  1  2  0 | 8N  * * |  1  1 0
sefa( . s2sns ) & |  3 |  0  2  1 |  * 8N * |  0  1 1
      .   sns     |  N |  0  0  N |  *  * 4 |  0  0 2
------------------+----+----------+---------+--------
      s2s2s .   &   4 |  2  4  0 |  4  0 0 | 2N  * *  tet
sefa( s2s2sns )     4 |  1  4  1 |  2  2 0 |  * 4N *  disphenoid
      . s2sns   &  2N |  0 2N 2N |  0 2N 2 |  *  * 4  n-ap

starting figure: x x xnx

s4o2sns (n>2)

demi( . . . . )   | 4N |  1  4  2 | 1  6  6 |  2 2  4
------------------+----+----------+---------+--------
      s4o . .     |  2 | 2N  *  * | 0  4  0 |  2 0  2  A*sqrt(2)
      s 2 s .   & |  2 |  * 8N  * | 0  2  2 |  1 1  2  sqrt(A2+B2)
sefa( . . sns )   |  2 |  *  * 4N | 1  0  2 |  0 2  1  B*x(2n)
------------------+----+----------+---------+--------
      .   sns     |  N |  0  0  N | 4  *  * |  0 2  0
sefa( s4o2s . ) & |  3 |  1  2  0 | * 8N  * |  1 0  1
sefa( s 2 sns )   |  3 |  0  2  1 | *  * 8N |  0 1  1
------------------+----+----------+---------+--------
      s4o2s .   &   4 |  2  4  0 | 0  4  0 | 2N *  *  tet
      s 2 sns      2N |  0 2N 2N | 2  0 2N |  * 4  *  n-ap
sefa( s4o2sns )     4 |  1  4  1 | 0  2  2 |  * * 4N  disphenoid

starting figure: x4o xnx

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