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A378713
Decimal expansion of the volume of a disdyakis dodecahedron with unit shorter edge length.
10
1, 6, 2, 8, 8, 9, 1, 9, 0, 8, 2, 9, 2, 3, 5, 2, 5, 0, 3, 8, 5, 0, 3, 1, 2, 2, 5, 0, 3, 6, 1, 9, 4, 4, 1, 0, 4, 5, 9, 9, 6, 7, 9, 7, 4, 4, 7, 3, 5, 7, 0, 2, 7, 2, 1, 7, 2, 4, 8, 7, 2, 2, 8, 3, 5, 7, 8, 3, 7, 0, 1, 3, 4, 1, 5, 1, 8, 7, 0, 4, 9, 5, 9, 7, 6, 5, 0, 6, 9, 2
OFFSET
2,2
COMMENTS
The disdyakis dodecahedron is the dual polyhedron of the truncated cuboctahedron (great rhombicuboctahedron).
FORMULA
Equals sqrt(3*(2194 + 1513*sqrt(2)))/7 = sqrt(6582 + 4539*A002193)/7.
Minimal polynomial: 49*x^4 - 13164*x^2 + 43218. - Amiram Eldar, May 14 2026
EXAMPLE
16.288919082923525038503122503619441045996797447357...
MATHEMATICA
First[RealDigits[Sqrt[6582 + 4539*Sqrt[2]]/7, 10, 100]]
(* Alternative: *)
First[RealDigits[PolyhedronData["DisdyakisDodecahedron", "Volume"], 10, 100]]
PROG
(PARI) sqrt(3*(2194 + 1513*sqrt(2)))/7 \\ Charles R Greathouse IV, Feb 05 2025
CROSSREFS
Cf. A378712 (surface area), A378714 (inradius), A378393 (midradius), A378715 (dihedral angle).
Cf. A377344 (volume of a truncated cuboctahedron (great rhombicuboctahedron) with unit edge length).
Cf. A002193.
Sequence in context: A259931 A333350 A332092 * A021163 A114866 A384279
KEYWORD
nonn,cons,easy
AUTHOR
Paolo Xausa, Dec 07 2024
STATUS
approved