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%I #8 Apr 10 2021 20:57:58
%S 6,2,9,0,5,4,1,6,2,9,7,8,4,0,4,2,3,0,8,6,1,8,0,6,7,8,2,6,9,4,4,1,2,3,
%T 6,8,8,4,4,6,3,2,5,8,1,7,8,5,5,5,9,3,9,5,6,2,5,2,3,4,6,6,4,6,7,5,2,7,
%U 0,6,5,7,2,9,3,2,7,1,8,1,0,4,2,3,9,8,5,4,1,5,3,7,4,3,5,5,8,4,7
%N Decimal expansion of x satisfying 6*x^2 - 1 = cot(x) and 0 < x < Pi.
%C See A201280 for a guide to related sequences. The Mathematica program includes a graph.
%e x=0.6290541629784042308618067826944123...
%t a = 6; c = -1;
%t f[x_] := a*x^2 + c; g[x_] := Cot[x]
%t Plot[{f[x], g[x]}, {x, 0, Pi/2}, {AxesOrigin -> {0, 0}}]
%t r = x /. FindRoot[f[x] == g[x], {x, .6, .7}, WorkingPrecision -> 110]
%t RealDigits[r] (* A201324 *)
%Y Cf. A201280.
%K nonn,cons
%O 0,1
%A _Clark Kimberling_, Nov 30 2011