cp's OEIS Frontend

A379133 Decimal expansion of the volume of a pentakis dodecahedron with unit shorter edge length.

%I A379133 #12 Feb 05 2025 10:25:44
%S A379133 1,3,4,5,8,5,6,9,3,6,6,3,1,8,7,1,4,2,2,3,6,4,2,9,6,4,1,2,7,5,3,9,1,5,
%T A379133 3,5,9,5,2,7,9,9,2,4,8,5,9,7,6,2,2,4,2,0,9,8,1,6,2,8,3,7,6,5,7,6,7,5,
%U A379133 4,1,9,8,8,0,6,8,6,8,2,2,5,6,7,4,1,1,1,6,1,1
%N A379133 Decimal expansion of the volume of a pentakis dodecahedron with unit shorter edge length.
%C A379133 The pentakis dodecahedron is the dual polyhedron of the truncated icosahedron.
%H A379133 Paolo Xausa, <a href="/A379133/b379133.txt">Table of n, a(n) for n = 2..10000</a>
%H A379133 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PentakisDodecahedron.html">Pentakis Dodecahedron</a>.
%H A379133 Wikipedia, <a href="https://en.wikipedia.org/wiki/Pentakis_dodecahedron">Pentakis dodecahedron</a>.
%H A379133 <a href="/index/Al#algebraic_02">Index entries for algebraic numbers, degree 2</a>.
%F A379133 Equals (5/36)*(41 + 25*sqrt(5)) = (5/36)*(41 + 25*A002163).
%e A379133 13.458569366318714223642964127539153595279924859762...
%t A379133 First[RealDigits[5/36*(41 + 25*Sqrt[5]), 10, 100]] (* or *)
%t A379133 First[RealDigits[PolyhedronData["PentakisDodecahedron", "Volume"], 10, 100]]
%o A379133 (PARI) (41 + 25*sqrt(5))*5/36 \\ _Charles R Greathouse IV_, Feb 05 2025
%Y A379133 Cf. A379132 (surface area), A379134 (inradius), A379135 (midradius), A379136 (dihedral angle).
%Y A379133 Cf. A377751 (volume of a truncated icosahedron with unit edge length).
%Y A379133 Cf. A002163.
%K A379133 nonn,cons,easy
%O A379133 2,2
%A A379133 _Paolo Xausa_, Dec 16 2024