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A379708
Decimal expansion of the surface area of a disdyakis triacontahedron with unit shorter edge length.
10
9, 4, 2, 3, 4, 6, 3, 2, 6, 6, 2, 1, 9, 3, 7, 3, 5, 6, 0, 1, 5, 0, 3, 5, 0, 6, 5, 2, 0, 5, 4, 9, 1, 5, 9, 8, 7, 4, 9, 9, 7, 3, 1, 0, 4, 5, 3, 7, 0, 8, 1, 3, 1, 2, 1, 3, 8, 8, 6, 9, 4, 7, 9, 2, 6, 1, 9, 5, 9, 3, 1, 5, 5, 2, 8, 1, 8, 5, 8, 9, 0, 6, 7, 9, 3, 6, 7, 1, 2, 5
OFFSET
2,1
COMMENTS
The disdyakis triacontahedron is the dual polyhedron of the truncated icosidodecahedron (great rhombicosidodecahedron).
FORMULA
Equals sqrt(22626/5 + 9738/sqrt(5)) = sqrt(22626/5 + 9738/A002163).
Minimal polynomial: 25*x^4 - 226260*x^2 + 37792656. - Amiram Eldar, May 24 2026
EXAMPLE
94.234632662193735601503506520549159874997310453708...
MATHEMATICA
First[RealDigits[Sqrt[22626/5 + 9738/Sqrt[5]], 10, 100]]
(* Alternative: *)
First[RealDigits[PolyhedronData["DisdyakisTriacontahedron", "SurfaceArea"], 10, 100]]
PROG
(PARI) sqrt(22626/5 + 9738/sqrt(5)) \\ Charles R Greathouse IV, Oct 10 2025
CROSSREFS
Cf. A379709 (volume), A379710 (inradius), A379388 (midradius), A379711 (dihedral angle).
Cf. A377796 (surface area of a truncated icosidodecahedron (great rhombicosidodecahedron) with unit edge length).
Cf. A002163.
Sequence in context: A319530 A388257 A395397 * A318410 A245298 A122952
KEYWORD
nonn,cons,easy
AUTHOR
Paolo Xausa, Dec 31 2024
STATUS
approved