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%I #10 Nov 26 2024 14:45:11
%S 6,0,2,7,3,4,2,0,3,9,9,5,6,9,3,9,9,0,3,3,0,9,2,9,2,9,1,6,5,1,1,4,3,5,
%T 2,1,4,0,6,1,2,6,5,9,2,6,2,5,6,5,5,0,4,6,1,7,2,5,5,0,8,9,0,9,3,1,3,2,
%U 8,7,4,0,9,8,0,4,6,1,2,7,1,9,6,0,0,6,7,4,3,0,3,1,1,6,0,5,2,8,1
%N Decimal expansion of x satisfying 4*x^2 = cot(x) and 0 < x < Pi.
%C See A201280 for a guide to related sequences. The Mathematica program includes a graph.
%H <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>.
%e 0.60273420399569399033092929165114352....
%t a = 4; c = 0;
%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] (* A201331 *)
%o (PARI) solve(x=0,1,4*x^2*tan(x)-1) \\ _Charles R Greathouse IV_, Nov 26 2024
%Y Cf. A201280.
%K nonn,cons
%O 0,1
%A _Clark Kimberling_, Nov 30 2011