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 A263180 #8 Jan 07 2021 07:30:52
%S A263180 1,4,6,1,6,8,1,3,4,9,2,0,8,0,4,0,0,7,3,6,2,0,0,6,7,0,6,5,1,4,9,9,3,6,
%T A263180 7,9,0,7,0,8,8,2,2,1,7,0,4,8,0,5,3,7,7,4,9,4,3,7,0,4,1,7,4,8,9,0,4,3,
%U A263180 2,9,3,6,0,5,2,4,3,2,1,4,8,8,5,0,3,9,2,9,7,2,0,3,7,8,8,0,2,6,0,6,9,7,2,5,1,8
%N A263180 Decimal expansion of a constant related to A263143 (negated).
%F A263180 Integral_{x=0..infinity} exp(-2*x)/(x*(1 - exp(-5*x))^2) - 1/(25*x^3) - 3/(25*x^2) - 29/(300*x*exp(x)) dx.
%F A263180 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 A263180 -0.146168134920804007362006706514993679070882217048053774943704174890...
%t A263180 NIntegrate[E^(-2*x)/(1-E^(-5*x))^2/x - 1/(25*x^3) - 3/(25*x^2) - 29*E^(-x)/(300*x), {x, 0, Infinity}, WorkingPrecision -> 120, MaxRecursion -> 100, PrecisionGoal -> 110]
%Y A263180 Cf. A263143, A263178, A263179, A263181.
%K A263180 nonn,cons
%O A263180 0,2
%A A263180 _Vaclav Kotesovec_, Oct 11 2015