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A179451
Decimal expansion of the surface area of an icosidodecahedron with side length 1.
21
2, 9, 3, 0, 5, 9, 8, 2, 8, 4, 4, 9, 1, 1, 9, 8, 9, 5, 4, 0, 7, 4, 5, 3, 7, 5, 4, 3, 6, 1, 9, 2, 6, 7, 7, 0, 2, 7, 6, 0, 2, 5, 1, 6, 3, 0, 9, 1, 7, 4, 2, 8, 3, 0, 9, 0, 7, 6, 4, 1, 7, 1, 3, 8, 1, 5, 4, 6, 0, 9, 2, 9, 9, 1, 0, 5, 1, 5, 9, 4, 9, 6, 1, 3, 9, 5, 0, 2, 5, 8, 3, 0, 4, 3, 7, 2, 9, 5, 7, 6, 4, 3, 0, 4, 6
OFFSET
2,1
COMMENTS
Icosidodecahedron: 32 faces, 30 vertices, and 60 edges.
Also the surface area of a pentagonal orthobirotunda (Johnson solid J_34) with unit edges. - Paolo Xausa, Oct 03 2025
FORMULA
Equals Sqrt(30*(10+3*sqrt(5)+sqrt(75+30*sqrt(5)))).
Minimal polynomial: x^8 - 1200*x^6 + 324000*x^4 - 27000000*x^2 + 324000000. - Amiram Eldar, May 24 2026
EXAMPLE
29.3059828449119895407453754361926770276025163091742830907641713815460...
MATHEMATICA
RealDigits[N[Sqrt[30*(10+3*Sqrt[5]+Sqrt[75+30*Sqrt[5]])], 200]]
PROG
(PARI) polrootsreal(x^8 - 1200*x^6 + 324000*x^4 - 27000000*x^2 + 324000000)[8] \\ Charles R Greathouse IV, Oct 30 2023
KEYWORD
nonn,cons,easy
AUTHOR
EXTENSIONS
Partially rewritten by Charles R Greathouse IV, Feb 03 2011
STATUS
approved