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 A198815 #8 Feb 07 2025 16:44:05
%S A198815 2,7,8,3,1,1,4,7,5,6,5,0,3,0,2,0,3,0,0,6,3,9,9,2,2,7,2,9,2,3,6,9,5,8,
%T A198815 5,1,8,5,9,8,8,1,3,0,7,0,3,5,6,5,4,2,1,3,4,2,4,9,6,8,8,7,3,8,8,0,8,9,
%U A198815 3,7,9,2,4,2,7,8,6,8,9,4,7,2,5,9,6,6,3,7,0,1,3,5,1,5,9,5,2,3,5
%N A198815 Decimal expansion of x>0 satisfying x^2+4*cos(x)=4.
%C A198815 See A198755 for a guide to related sequences. The Mathematica program includes a graph.
%H A198815 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>.
%e A198815 2.7831147565030203006399227292369585185988130...
%t A198815 a = 1; b = 4; c = 4;
%t A198815 f[x_] := a*x^2 + b*Cos[x]; g[x_] := c
%t A198815 Plot[{f[x], g[x]}, {x, -3, 3}, {AxesOrigin -> {0, 0}}]
%t A198815 r = x /. FindRoot[f[x] == g[x], {x, 2.7, 2.8}, WorkingPrecision -> 110]
%t A198815 RealDigits[r] (* A198815 *)
%Y A198815 Cf. A198755.
%K A198815 nonn,cons
%O A198815 1,1
%A A198815 _Clark Kimberling_, Oct 30 2011