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 A199390 #8 Feb 07 2025 19:55:58
%S A199390 4,5,0,2,3,5,3,1,6,4,0,0,3,2,0,4,4,6,9,8,0,7,5,5,7,4,5,3,7,6,0,7,5,4,
%T A199390 9,5,0,4,8,6,0,6,9,0,2,8,4,7,2,6,6,4,8,6,1,4,5,6,6,2,4,1,2,5,1,3,8,1,
%U A199390 4,5,4,2,4,3,0,1,2,2,0,7,1,4,4,5,5,7,5,2,8,3,1,8,7,5,1,0,7,4,8
%N A199390 Decimal expansion of x>0 satisfying 3*x^2+2*x*sin(x)=1.
%C A199390 See A199370 for a guide to related sequences. The Mathematica program includes a graph.
%H A199390 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>.
%e A199390 0.45023531640032044698075574537607549504860690...
%t A199390 a = 3; b = 2; c = 1;
%t A199390 f[x_] := a*x^2 + b*x*Sin[x]; g[x_] := c
%t A199390 Plot[{f[x], g[x]}, {x, -1, Pi}, {AxesOrigin -> {0, 0}}]
%t A199390 r = x /. FindRoot[f[x] == g[x], {x, .45, .46}, WorkingPrecision -> 110]
%t A199390 RealDigits[r] (* A199390 *)
%Y A199390 Cf. A199370.
%K A199390 nonn,cons
%O A199390 0,1
%A A199390 _Clark Kimberling_, Nov 06 2011