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 A202499 #9 Feb 07 2025 16:44:07
%S A202499 3,4,9,9,6,9,6,3,1,6,5,4,6,7,9,9,8,6,6,6,2,8,9,9,0,2,3,5,1,7,6,3,2,6,
%T A202499 3,4,8,6,3,1,5,5,6,4,7,9,0,2,1,1,3,8,1,7,6,4,4,2,9,0,5,2,7,7,7,2,2,1,
%U A202499 6,3,5,0,1,4,8,1,4,7,6,5,2,6,2,8,5,5,9,5,5,5,6,0,7,4,7,8,2,2,4
%N A202499 Decimal expansion of x satisfying x=e^(-3x).
%C A202499 See A202348 for a guide to related sequences. The Mathematica program includes a graph.
%e A202499 x=0.3499696316546799866628990235176326348631556...
%t A202499 u = -3; v = 0;
%t A202499 f[x_] := x; g[x_] := E^(u*x + v)
%t A202499 Plot[{f[x], g[x]}, {x, -1, 1}, {AxesOrigin -> {0, 0}}]
%t A202499 r = x /. FindRoot[f[x] == g[x], {x, .3, .4}, WorkingPrecision -> 110]
%t A202499 RealDigits[r] (* A202499 *)
%t A202499 RealDigits[ ProductLog[3]/3, 10, 99] // First (* _Jean-François Alcover_, Feb 27 2013 *)
%Y A202499 Cf. A202348.
%K A202499 nonn,cons
%O A202499 0,1
%A A202499 _Clark Kimberling_, Dec 20 2011