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 A364931 #11 Feb 16 2025 08:34:06
%S A364931 6,5,9,0,4,6,0,6,8,4,0,7,4,0,6,6,6,0,9,8,4,3,8,6,4,9,5,9,2,8,8,6,7,5,
%T A364931 5,1,6,9,8,0,9,0,3,3,0,3,5,7,1,1,5,1,8,8,4,8,9,2,9,4,6,3,0,8,0,4,2,2,
%U A364931 4,1,1,3,0,4,2,4,2,9,7,5,7,5,7,9,0,3,4,7,3,5,6,4,8,2,8,2,0,1,0,5
%N A364931 Decimal expansion of the solution to 1 / (1 + e^(-x)) = x.
%C A364931 Fixed point of sigmoid (standard logistic function) as well as its inverse (logit).
%H A364931 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/SigmoidFunction.html">Sigmoid Function</a>.
%H A364931 Wikipedia, <a href="https://en.wikipedia.org/wiki/Logistic_function">Logistic Function</a>.
%e A364931 0.6590460684074066...
%p A364931 Digits:=100: fsolve(1/(1+exp(-x))-x, x);
%t A364931 RealDigits[FindRoot[1/(1+Exp[-x])-x, {x, 0.6}, WorkingPrecision -> 100][[1, 2]], 10, 100][[1]]
%o A364931 (PARI) default(realprecision, 100); solve(x=0.4,0.7,1/(1+exp(-x))-x)
%K A364931 nonn,cons
%O A364931 0,1
%A A364931 _Michal Paulovic_, Aug 13 2023