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A378712
Decimal expansion of the surface area of a disdyakis dodecahedron with unit shorter edge length.
10
3, 2, 0, 6, 6, 7, 3, 4, 0, 1, 0, 5, 3, 1, 9, 4, 4, 4, 1, 3, 3, 4, 9, 8, 2, 3, 8, 7, 4, 8, 9, 5, 7, 2, 3, 4, 6, 2, 8, 6, 3, 4, 9, 5, 8, 5, 1, 5, 5, 3, 2, 5, 4, 5, 6, 0, 5, 3, 0, 9, 5, 7, 9, 9, 5, 3, 6, 2, 4, 8, 9, 0, 0, 6, 0, 2, 1, 1, 0, 7, 4, 3, 5, 3, 1, 8, 1, 5, 7, 1
OFFSET
2,1
COMMENTS
The disdyakis dodecahedron is the dual polyhedron of the truncated cuboctahedron (great rhombicuboctahedron).
FORMULA
Equals (6/7)*sqrt(783 + 436*sqrt(2)) = (6/7)*sqrt(783 + 436*A002193).
Minimal polynomial: 49*x^4 - 56376*x^2 + 6159888. - Amiram Eldar, May 17 2026
EXAMPLE
32.066734010531944413349823874895723462863495851553...
MATHEMATICA
First[RealDigits[6/7*Sqrt[783 + 436*Sqrt[2]], 10, 100]] (* or *)
First[RealDigits[PolyhedronData["DisdyakisDodecahedron", "SurfaceArea"], 10, 100]]
PROG
(PARI) sqrt(783 + 436*sqrt(2))*6/7 \\ Charles R Greathouse IV, Feb 05 2025
CROSSREFS
Cf. A378713 (volume), A378714 (inradius), A378393 (midradius), A378715 (dihedral angle).
Cf. A377343 (surface area of a truncated cuboctahedron (great rhombicuboctahedron) with unit edge length).
Cf. A002193.
Sequence in context: A049780 A159584 A257653 * A385577 A246834 A319730
KEYWORD
nonn,cons,easy
AUTHOR
Paolo Xausa, Dec 06 2024
STATUS
approved