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 A201292 #11 Jan 30 2025 16:02:34
%S A201292 5,1,1,0,2,8,9,6,8,8,6,7,1,8,8,6,5,4,9,8,9,5,9,1,1,4,8,1,1,1,0,4,9,3,
%T A201292 6,7,2,8,6,0,7,2,8,6,6,0,2,7,8,4,9,4,5,3,8,8,1,2,8,3,1,8,8,7,6,0,8,9,
%U A201292 4,3,3,9,7,9,1,9,1,4,1,1,7,4,2,6,6,6,7,8,0,9,7,1,3,8,5,3,2,5,1
%N A201292 Decimal expansion of x satisfying 3*x^2 + 1 = cot(x) and 0 < x < Pi.
%C A201292 See A201280 for a guide to related sequences. The Mathematica program includes a graph.
%H A201292 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>.
%e A201292 0.5110289688671886549895911481110493672...
%t A201292 a = 3; c = 1;
%t A201292 f[x_] := a*x^2 + c; g[x_] := Cot[x]
%t A201292 Plot[{f[x], g[x]}, {x, 0, Pi/2}, {AxesOrigin -> {0, 0}}]
%t A201292 r = x /. FindRoot[f[x] == g[x], {x, .5, .6}, WorkingPrecision -> 110]
%t A201292 RealDigits[r] (* A201292 *)
%Y A201292 Cf. A201280.
%K A201292 nonn,cons
%O A201292 0,1
%A A201292 _Clark Kimberling_, Nov 29 2011