A201336 - OEIS

%I #10 Jan 30 2025 15:57:57

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

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

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

%N Decimal expansion of x satisfying 9*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 0.4685405476891286591229277857617431311460...

%t a = 9; 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, .4, .5}, WorkingPrecision -> 110]

%t RealDigits[r]   (* A201336 *)

%Y Cf. A201280.

%K nonn,cons,changed

%O 0,1

%A _Clark Kimberling_, Nov 30 2011