login
A347903
Decimal expansion of the surface area of the unit trihyperboloid.
1
1, 8, 7, 6, 9, 3, 9, 6, 2, 6, 7, 4, 5, 3, 8, 9, 2, 0, 0, 0, 4, 3, 1, 9, 0, 3, 8, 1, 1, 1, 0, 7, 3, 0, 0, 2, 8, 5, 0, 1, 5, 0, 3, 2, 7, 8, 3, 7, 4, 2, 3, 5, 3, 7, 2, 1, 1, 9, 9, 4, 9, 8, 8, 5, 3, 1, 1, 6, 2, 3, 6, 6, 1, 7, 6, 7, 0, 1, 8, 5, 8, 6, 8, 3, 3, 6, 4
OFFSET
2,2
LINKS
Eric Weisstein's World of Mathematics, Trihyperboloid
FORMULA
Can be given as a closed-form expression involving logs, polylogs, and polygammas (which probably simplifies further).
EXAMPLE
18.769396267453...
MATHEMATICA
First[RealDigits[N[24(Sqrt[3]-1)-2Pi+12Sqrt[2]Re[NIntegrate[ArcTanh[x]/((2x^2-1)Sqrt[(1-x^(-2))/2]), {x, Sqrt[3/2], Infinity}, WorkingPrecision->100]], 90]]] (* Stefano Spezia, Sep 19 2021 *)
CROSSREFS
Cf. A257872 (volume of the unit trihyperboloid).
Sequence in context: A132037 A247095 A124597 * A214023 A154209 A115373
KEYWORD
nonn,cons
AUTHOR
Eric W. Weisstein, Sep 18 2021
STATUS
approved