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 A199179 #13 Feb 07 2025 16:44:05
%S A199179 9,4,4,9,4,8,3,2,9,1,0,3,5,4,6,9,6,4,9,4,5,9,2,7,6,4,0,3,7,8,3,4,5,5,
%T A199179 5,1,6,8,6,9,7,2,5,6,5,9,9,0,0,8,1,1,2,3,4,6,4,8,9,1,2,1,6,0,6,7,5,6,
%U A199179 5,8,7,8,0,9,6,7,9,2,3,2,9,0,3,1,2,8,2,8,4,2,8,9,8,9,7,8,9,9,6
%N A199179 Decimal expansion of x > 0 satisfying x^2 + 2*x*cos(x) = 2.
%C A199179 See A199170 for a guide to related sequences. The Mathematica program includes a graph.
%H A199179 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>.
%e A199179 negative: -1.493519280868891056556339509934781825...
%e A199179 positive: 0.94494832910354696494592764037834555...
%t A199179 a = 1; b = 2; c = 2;
%t A199179 f[x_] := a*x^2 + b*x*Cos[x]; g[x_] := c
%t A199179 Plot[{f[x], g[x]}, {x, -5, 3}, {AxesOrigin -> {0, 0}}]
%t A199179 r = x /. FindRoot[f[x] == g[x], {x, -1.5, -1.4}, WorkingPrecision -> 110]
%t A199179 RealDigits[r] (* A199178 *)
%t A199179 r = x /. FindRoot[f[x] == g[x], {x, .2, .53}, WorkingPrecision -> 110]
%t A199179 RealDigits[r] (* A199179 *)
%Y A199179 Cf. A199170, A199178.
%K A199179 nonn,cons
%O A199179 0,1
%A A199179 _Clark Kimberling_, Nov 04 2011
%E A199179 a(95) onwards corrected by _Georg Fischer_, Aug 03 2021