A373023 - OEIS

%I #4 Jul 22 2024 15:27:55

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

%T 7,1,4,5,8,5,0,7,4,5,9,4,7,1,0,8,3,3,9,7,3,0,8,6,1,3,0,8,5,7,7,7,4,3,

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

%N Decimal expansion of Sum_{k>=0} sin(3k*Pi/5)/2^k.

%F Equals sqrt((5 + sqrt(5)]/(8 + 2 sqrt(5)).

%F Equals (-1)*Sum_{k>=0} sin(7 k*Pi/5)/2^k.

%F Minimal polynomial: 5 - 65 x^2 + 121 x^4.

%e 0.30501800805463899236580110742909107145...

%t {b, m, h} = {2, 5, 3}; s = Sum[Sin[ h k Pi/m]/b^k, {k, 0, Infinity}]

%t d = N[s, 100]

%t First[RealDigits[d], 100]

%Y Cf. A373021 (includes guide to related sequences).

%K nonn,cons

%O 0,1

%A _Clark Kimberling_, Jul 20 2024