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%I #12 Jan 07 2021 07:29:42
%S 1,8,8,7,0,8,1,9,1,9,7,9,5,2,8,5,3,2,3,7,6,4,1,0,0,9,8,6,4,9,2,0,7,9,
%T 7,3,5,9,2,1,1,4,4,6,7,2,6,8,4,2,9,2,2,1,5,0,9,4,1,7,4,3,3,7,8,2,3,2,
%U 3,7,2,1,3,7,1,8,0,6,7,4,7,1,3,9,4,6,9,7,4,1,6,1,8,7,0,1,6,2,5,8,3,2,8,1,7,9
%N Decimal expansion of a constant related to A262876 and A262946 (negated).
%F Integral_{x=0..infinity} 1/x*(exp(-2*x)/(1 - exp(-3*x))^2 - 1/(9*x^2) - 1/(9*x) + exp(-x)/36) dx.
%F exp(3*(A263030+A263031)) = A^2 * Gamma(1/3) / (3^(11/12) * exp(1/6) * sqrt(2*Pi)), where A = A074962 is the Glaisher-Kinkelin constant.
%e -0.18870819197952853237641009864920797359211446726842922150941743378232...
%t NIntegrate[1/x*(Exp[-2*x]/(1 - Exp[-3*x])^2 - 1/(9*x^2) - 1/(9*x) + Exp[-x]/36), {x, 0, Infinity}, WorkingPrecision -> 120, MaxRecursion -> 100, PrecisionGoal -> 110]
%Y Cf. A262876, A262877, A262946, A262947, A263031, A075700, A084448, A263406, A263415.
%K nonn,cons
%O 0,2
%A _Vaclav Kotesovec_, Oct 08 2015