A201320 - OEIS

%I #8 Apr 10 2021 20:58:51

%S 9,3,3,0,2,7,6,7,4,6,6,6,1,7,7,2,5,5,9,0,6,8,7,9,1,3,5,6,1,3,0,5,1,0,

%T 6,5,4,1,1,9,0,4,1,2,7,1,1,1,3,6,0,9,4,0,9,5,0,9,0,2,0,6,6,2,6,0,2,2,

%U 1,7,4,7,3,3,3,4,1,4,5,0,0,9,1,1,2,2,1,6,8,9,6,9,7,3,6,3,0,7,2

%N Decimal expansion of x satisfying 2*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=0.93302767466617725590687913561305106...

%t a = 2; 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, .9, 1.0}, WorkingPrecision -> 110]

%t RealDigits[r]   (* A201320 *)

%Y Cf. A201280.

%K nonn,cons

%O 0,1

%A _Clark Kimberling_, Nov 30 2011