7) truncated tetrahedron 2 3|3 [16,6] dual: triakistetrahedron (6.6.3), tetrahedral group A4, χ=2, D=1 V=12, E=18, F=8=4{6}+4{3} α γ a b c ρ/R r/ρ l/ρ h/r {6} 30.0 73.2213 25.24 58.52 54.74 0.904534 0.577350 0.471405 1.414214 {3} 60.0 33.5573 25.24 29.50 15.79 0.904534 0.962250 0.471405 0.282843