This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A263181 #8 Jan 07 2021 07:31:08
%S A263181 1,8,6,3,8,2,6,9,0,6,2,4,7,5,2,6,3,0,3,9,1,3,6,8,3,6,4,6,2,9,9,1,8,4,
%T A263181 8,3,3,8,4,4,2,4,0,8,6,3,4,1,7,6,4,4,0,9,1,4,6,9,2,3,6,8,6,0,4,1,9,8,
%U A263181 8,7,2,9,6,2,8,8,0,7,2,5,4,4,2,9,1,6,5,2,2,8,7,3,4,4,0,1,9,4,3,6,4,9,4,4,1,8
%N A263181 Decimal expansion of a constant related to A263144.
%F A263181 Integral_{x=0..infinity} exp(-x)/(x*(1 - exp(-5*x))^2) - 1/(25*x^3) - 4/(25*x^2) - 71/(300*x*exp(x)) dx.
%F A263181 A263178 + A263179 + A263180 + A263181 = (log(Gamma(1/5)^3 / ((1+sqrt(5)) * Pi * Gamma(3/5) * 5^(29/12))) - 4*Zeta'(-1))/5 = -0.2745843324986204888923185745... . - _Vaclav Kotesovec_, Oct 12 2015
%e A263181 0.1863826906247526303913683646299184833844240863417644091469236860419...
%t A263181 NIntegrate[E^(-x)/(1-E^(-5*x))^2/x - 1/(25*x^3) - 4/(25*x^2) - 71*E^(-x)/(300*x), {x, 0, Infinity}, WorkingPrecision -> 120, MaxRecursion -> 100, PrecisionGoal -> 110]
%Y A263181 Cf. A263144, A263178, A263179, A263180.
%K A263181 nonn,cons
%O A263181 0,2
%A A263181 _Vaclav Kotesovec_, Oct 11 2015