173_RT_2.7527

2 f^2/Sqrt[1+f^2] = 2.75276

Ez az 1 élű RT laptávolsága. This is the distance of two opposite faces of RT having edge lenght 1. RT with face cobnection can be placed at the vertices of many polyhedra (How many?) E.g. 12 RT at vertices of ico, with RH in the middle.

see also: http://www.kabai.hu/gallery/ima2010-budapest

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