cp's OEIS Frontend

A386689 Decimal expansion of the volume of a diminished rhombicosidodecahedron with unit edges.

%I A386689 #9 Jul 31 2025 08:43:06
%S A386689 3,9,2,9,1,2,7,8,4,6,4,1,6,4,7,7,3,9,3,4,3,4,9,2,2,9,6,8,5,2,4,8,1,5,
%T A386689 2,7,8,5,6,3,2,2,3,1,9,0,3,1,7,0,3,9,8,1,8,5,1,0,4,7,4,1,8,7,5,3,6,1,
%U A386689 3,5,4,9,9,7,4,0,6,9,1,0,7,6,1,3,9,6,3,9,6,3
%N A386689 Decimal expansion of the volume of a diminished rhombicosidodecahedron with unit edges.
%C A386689 The diminished rhombicosidodecahedron is Johnson solid J_76.
%C A386689 Also the volume of a paragyrate diminished rhombicosidodecahedron, a metagyrate diminished rhombicosidodecahedron and a bigyrate diminished rhombicosidodecahedron (Johnson solids J_77, J_78 and J_79, respectively) with unit edges.
%H A386689 Paolo Xausa, <a href="/A386689/b386689.txt">Table of n, a(n) for n = 2..10000</a>
%H A386689 Wikipedia, <a href="https://en.wikipedia.org/wiki/Bigyrate_diminished_rhombicosidodecahedron">Bigyrate diminished rhombicosidodecahedron</a>.
%H A386689 Wikipedia, <a href="https://en.wikipedia.org/wiki/Diminished_rhombicosidodecahedron">Diminished rhombicosidodecahedron</a>.
%H A386689 Wikipedia, <a href="https://en.wikipedia.org/wiki/Metagyrate_diminished_rhombicosidodecahedron">Metagyrate diminished rhombicosidodecahedron</a>.
%H A386689 Wikipedia, <a href="https://en.wikipedia.org/wiki/Paragyrate_diminished_rhombicosidodecahedron">Paragyrate diminished rhombicosidodecahedron</a>.
%F A386689 Equals 115/6 + 9*sqrt(5) = 115/6 + 9*A002163.
%F A386689 Equals A185093 - A179590.
%F A386689 Equals the largest root of 36*x^2 - 1380*x - 1355.
%e A386689 39.29127846416477393434922968524815278563223190317...
%t A386689 First[RealDigits[115/6 + 9*Sqrt[5], 10, 100]] (* or *)
%t A386689 First[RealDigits[PolyhedronData["J76", "Volume"], 10, 100]]
%Y A386689 Cf. A386690 (surface area).
%Y A386689 Cf. A002163, A179590, A185093, A386691, A386693.
%K A386689 nonn,cons,easy
%O A386689 2,1
%A A386689 _Paolo Xausa_, Jul 29 2025