Acronym ...
Name noble {9,3} modwrap within srid
 
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Circumradius sqrt[sqrt(5)+11/4] = 2.232951
Confer
uniform relative:
srid  
general polytopal classes:
noble   isogonals  

This noble polyhedron can be obtained as a faceting of srid. In fact the shorter edges are just using the diagonals of the srid's squares. So that, if taking the srid edges, which are pseudo edges in here, would be unity, then the shorter edges of these enneagons clearly are of length S = sqrt(2) = 0.707107, while the longer ones would be the tip-to-tip distances of a pentagon-square-pentagon patch in srid, thus that distance works out as L = 2+f = (5+sqrt(5))/2 = 3.618034.

The validity of this srid faceting is based on the fact that within srid, when oriented triangle first, then the bases of the adjacent pentagons and the tips of the neighbouring triangles will both be at the same level: these 9 points would outline the here being used enneagon [(S,S,L)3]/2, as highlighted in the above picture.


Incidence matrix

60 |  2  1 |  3
---+-------+---
 2 | 60  * |  2  S
 2 |  * 30 |  2  L
---+-------+---
 9 |  6  3 | 20  [(S,S,L)3]/2

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