OFFSET
1,3
COMMENTS
Multiplication with Pi^2/4 gives 2.554057.. = integral_{x=0..infinity} I_0(x) *K_0(x)^2 dx, where I and K are Modified Bessel Functions.
FORMULA
Square of A243308.
From Vaclav Kotesovec, Apr 10 2016: (Start)
Equals 3^(1/2) * Gamma(1/3)^6 / (2^(8/3) * Pi^4).
Equals Gamma(1/6)^3 / (3 * 2^(5/3) * Pi^(5/2)).
(End)
EXAMPLE
1.0351206614256489810459575514...
MAPLE
evalf(4*EllipticK(sqrt(2-sqrt(3))/2)^2 / Pi^2, 120); # Vaclav Kotesovec, Apr 10 2016
MATHEMATICA
RealDigits[HypergeometricPFQ[{1/2, 1/2, 1/2}, {1, 1}, 1/4], 10, 120][[1]] (* Vaclav Kotesovec, Apr 10 2016 *)
RealDigits[4*EllipticK[(2 - Sqrt[3])/4]^2 / Pi^2, 10, 120][[1]] (* Vaclav Kotesovec, Apr 10 2016 *)
CROSSREFS
KEYWORD
cons,nonn
AUTHOR
R. J. Mathar, Oct 19 2015
STATUS
approved