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 A197738 #6 Mar 30 2012 18:57:53
%S A197738 5,5,0,0,0,9,3,4,9,9,2,7,2,6,1,5,6,6,6,6,4,9,5,3,6,1,9,4,7,1,7,2,9,2,
%T A197738 6,1,1,6,7,2,8,5,0,9,2,4,3,5,7,9,3,7,8,4,5,7,0,9,3,9,2,2,0,4,2,5,2,6,
%U A197738 0,4,4,5,2,5,2,4,4,5,3,3,2,8,5,3,9,2,4,4,5,4,3,1,6,4,9,6,4,4,7
%N A197738 Decimal expansion of x>0 having x^2+x=cos(x).
%C A197738 For a discussion and guide to related sequences, see A197737.
%e A197738 negative: -1.25115183522076481159287006878816185994...
%e A197738 positive: 0.55000934992726156666495361947172926116...
%t A197738 a = 1; b = 1; c = 1;
%t A197738 f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
%t A197738 Plot[{f[x], g[x]}, {x, -2, 1}]
%t A197738 r1 = x /. FindRoot[f[x] == g[x], {x, -1.26, -1.25}, WorkingPrecision -> 110]
%t A197738 RealDigits[r1] (* A197737 *)
%t A197738 r1 = x /. FindRoot[f[x] == g[x], {x, .55, .551}, WorkingPrecision -> 110]
%t A197738 RealDigits[r1] (* A197738 *)
%Y A197738 Cf. A197737.
%K A197738 nonn,cons
%O A197738 0,1
%A A197738 _Clark Kimberling_, Oct 20 2011