A333188 - OEIS

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

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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