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 A201281 #10 Jan 30 2025 15:46:08
%S A201281 4,2,9,3,2,7,9,4,1,7,9,4,5,8,6,4,3,6,7,9,2,8,3,2,6,2,2,9,1,3,0,2,8,5,
%T A201281 3,1,4,3,2,5,1,6,6,6,0,2,1,0,8,2,5,6,4,6,5,8,6,7,1,6,5,5,2,6,5,5,8,6,
%U A201281 7,2,9,9,7,1,5,1,2,3,2,6,8,8,8,8,2,5,3,6,5,6,0,9,9,0,8,3,5,2,1
%N A201281 Decimal expansion of x satisfying x^2 + 2 = cot(x) and 0 < x < Pi.
%C A201281 See A201280 for a guide to related sequences. The Mathematica program includes a graph.
%H A201281 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>.
%e A201281 0.42932794179458643679283262291302853143...
%t A201281 a = 1; c = 2;
%t A201281 f[x_] := a*x^2 + c; g[x_] := Cot[x]
%t A201281 Plot[{f[x], g[x]}, {x, 0, Pi/2}, {AxesOrigin -> {0, 0}}]
%t A201281 r = x /. FindRoot[f[x] == g[x], {x, .42, .43}, WorkingPrecision -> 110]
%t A201281 RealDigits[r] (* A201281 *)
%Y A201281 Cf. A201280.
%K A201281 nonn,cons
%O A201281 0,1
%A A201281 _Clark Kimberling_, Nov 29 2011