A333188 a(n) = [2^n csc(1/n)] - [2^n cot(1/n)], where [ ] = floor.

1, 1, 1, 2, 4, 5, 10, 16, 28, 52, 94, 170, 316, 586, 1093, 2048, 3856, 7284, 13800, 26220, 49942, 95341, 182390, 349576, 671178, 1290714, 2485798, 4793999, 9257313, 17897354, 34639837, 67114326, 130160485, 252663350, 490886799, 954498552, 1857396219

Offset

1,4

Links

Table of n, a(n) for n=1..37.

Formula

a(n) = [2^n csc(1/n)] - [2^n cot(1/n)], where [ ] = floor.

Mathematica

z = 50; u = Table[Floor[2^n Csc[1/n]], {n, 1, z}] (* A333186 *)
v = Table[Floor[2^n Cot[1/n]], {n, 1, z}] (* A333187 *)
u - v  (* A333188 *)
w = Table[Floor[2^n Csc[1/n] - 2^n Cot[1/n]], {n, 1, z}];
u - v - w (* A333189 *)

Crossrefs

Cf. A333186, A333187, A333189.

Sequence in context: A299492 A253198 A138856 * A018401 A049332 A335206

Adjacent sequences: A333185 A333186 A333187 * A333189 A333190 A333191

Keyword

nonn,easy

Author

Clark Kimberling, Mar 11 2020

Status

approved