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 A198841 #8 Feb 07 2025 16:44:05
%S A198841 1,7,8,0,1,1,7,2,2,3,4,1,3,3,4,6,8,8,9,5,9,0,3,8,5,8,7,8,9,0,2,8,3,5,
%T A198841 8,8,2,5,4,6,2,0,1,9,4,0,3,4,4,7,7,3,5,4,7,0,5,6,8,9,9,7,1,0,4,6,8,8,
%U A198841 4,3,4,3,5,8,3,2,6,7,0,9,7,7,0,2,8,8,5,3,0,2,8,5,8,8,8,7,2,4,0
%N A198841 Decimal expansion of x>0 satisfying x^2-4*cos(x)=4.
%C A198841 See A198755 for a guide to related sequences. The Mathematica program includes a graph.
%H A198841 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>.
%e A198841 1.780117223413346889590385878902835882546201940...
%t A198841 a = 1; b = -4; c = 4;
%t A198841 f[x_] := a*x^2 + b*Cos[x]; g[x_] := c
%t A198841 Plot[{f[x], g[x]}, {x, -3, 3}, {AxesOrigin -> {0, 0}}]
%t A198841 r = x /. FindRoot[f[x] == g[x], {x, 1.7, 1.8}, WorkingPrecision -> 110]
%t A198841 RealDigits[r] (* A198841 *)
%Y A198841 Cf. A198755.
%K A198841 nonn,cons
%O A198841 1,2
%A A198841 _Clark Kimberling_, Oct 30 2011