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A379132
Decimal expansion of the surface area of a pentakis dodecahedron with unit shorter edge length.
5
2, 7, 9, 3, 5, 2, 4, 9, 6, 0, 0, 7, 0, 0, 7, 9, 3, 1, 0, 5, 8, 1, 0, 1, 9, 1, 2, 7, 9, 9, 6, 3, 6, 8, 0, 7, 0, 5, 2, 5, 7, 7, 8, 6, 1, 0, 9, 0, 7, 3, 6, 2, 6, 2, 5, 3, 5, 8, 6, 5, 9, 8, 4, 3, 0, 7, 7, 6, 1, 1, 3, 9, 5, 8, 0, 3, 1, 2, 7, 3, 3, 1, 2, 7, 0, 1, 6, 9, 7, 5
OFFSET
2,1
COMMENTS
The pentakis dodecahedron is the dual polyhedron of the truncated icosahedron.
LINKS
Eric Weisstein's World of Mathematics, Pentakis Dodecahedron.
FORMULA
Equals (5/3)*sqrt((421 + 63*sqrt(5))/2) = (5/3)*sqrt((421 + 63*A002163)/2).
EXAMPLE
27.93524960070079310581019127996368070525778610907...
MATHEMATICA
First[RealDigits[5/3*Sqrt[(421 + 63*Sqrt[5])/2], 10, 100]] (* or *)
First[RealDigits[PolyhedronData["PentakisDodecahedron", "SurfaceArea"], 10, 100]]
CROSSREFS
Cf. A379133 (volume), A379134 (inradius), A379135 (midradius), A379136 (dihedral angle).
Cf. A377750 (surface area of a truncated icosahedron with unit edge length).
Cf. A002163.
Sequence in context: A198122 A021362 A371803 * A246672 A011054 A276140
KEYWORD
nonn,cons,easy,new
AUTHOR
Paolo Xausa, Dec 16 2024
STATUS
approved