A333187 a(n) = floor(2^n cot(1/n)).

1, 7, 23, 62, 157, 380, 889, 2037, 4589, 10205, 22465, 49038, 106285, 228985, 490791, 1047210, 2225653, 4713736, 9952272, 20954040, 44006898, 92211129, 192816394, 402420140, 838413359, 1743970009, 3622221495, 7512996836, 15563085028, 32200323371, 66548900263

Offset

1,2

Links

Table of n, a(n) for n=1..31.

Formula

a(n) = floor(2^n cot(1/n)).

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, A333188, A333189.

Sequence in context: A211644 A077037 A201110 * A220509 A003261 A306971

Adjacent sequences: A333184 A333185 A333186 * A333188 A333189 A333190

Keyword

nonn,easy

Author

Clark Kimberling, Mar 11 2020

Status

approved