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A377296
Decimal expansion of 24*arctan(sqrt(2)).
3
2, 2, 9, 2, 7, 5, 9, 8, 8, 3, 4, 9, 8, 8, 2, 2, 2, 6, 7, 5, 9, 3, 2, 5, 7, 0, 4, 6, 0, 3, 7, 8, 1, 8, 6, 1, 0, 1, 8, 4, 1, 9, 5, 2, 6, 8, 0, 2, 4, 0, 1, 3, 1, 7, 8, 3, 0, 3, 2, 7, 5, 5, 1, 0, 3, 7, 2, 5, 8, 8, 9, 1, 0, 1, 6, 9, 5, 4, 3, 4, 9, 2, 9, 2, 9, 7, 3, 9, 8, 4
OFFSET
2,1
COMMENTS
Dehn invariant of a regular octahedron and (small) rhombicuboctahedron with unit edge and (negated) of a cuboctahedron and truncated cube with unit edge.
LINKS
Eric Weisstein's World of Mathematics, Dehn Invariant.
Eric Weisstein's World of Mathematics, Cuboctahedron.
Eric Weisstein's World of Mathematics, Regular Octahedron.
Eric Weisstein's World of Mathematics, Small Rhombicuboctahedron.
Eric Weisstein's World of Mathematics, Truncated Cube.
FORMULA
Equals 24*A195696 = 2*A377277.
EXAMPLE
22.9275988349882226759325704603781861018419526802...
MATHEMATICA
First[RealDigits[24*ArcTan[Sqrt[2]], 10, 100]] (* or *)
First[RealDigits[PolyhedronData["Octahedron", "DehnInvariant"], 10, 100]]
PROG
(PARI) 24*atan(sqrt(2)) \\ Charles R Greathouse IV, Nov 20 2024
CROSSREFS
Sequence in context: A037289 A037290 A155936 * A167594 A108462 A327859
KEYWORD
nonn,cons,easy
AUTHOR
Paolo Xausa, Oct 24 2024
STATUS
approved