cp's OEIS Frontend

A198927 Decimal expansion of x>0 satisfying 3*x^2-2*cos(x)=-1.

%I A198927 #8 Feb 07 2025 19:47:59
%S A198927 5,0,1,3,0,3,0,3,9,7,5,5,1,2,4,8,7,8,3,2,2,1,2,0,7,9,5,6,8,8,6,4,7,6,
%T A198927 4,7,1,8,1,5,9,5,8,3,7,2,0,8,9,4,4,4,7,1,0,6,1,5,0,7,4,8,8,4,3,4,5,3,
%U A198927 7,5,0,0,9,6,2,1,3,8,0,2,2,3,2,6,9,5,7,9,3,6,6,9,0,3,1,7,8,5,2
%N A198927 Decimal expansion of x>0 satisfying 3*x^2-2*cos(x)=-1.
%C A198927 See A198755 for a guide to related sequences. The Mathematica program includes a graph.
%H A198927 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>.
%e A198927 0.5013030397551248783221207956886476471815...
%t A198927 a = 3; b = -2; c = -1;
%t A198927 f[x_] := a*x^2 + b*Cos[x]; g[x_] := c
%t A198927 Plot[{f[x], g[x]}, {x, -2, 2}, {AxesOrigin -> {0, 0}}]
%t A198927 r = x /. FindRoot[f[x] == g[x], {x, .5, .51}, WorkingPrecision -> 110]
%t A198927 RealDigits[r]  (* A198927 *)
%Y A198927 Cf. A198755.
%K A198927 nonn,cons
%O A198927 0,1
%A A198927 _Clark Kimberling_, Oct 31 2011