A332431 a(n) = floor(2^n/(-1 + cot(1/n))).

-6, 4, 4, 5, 8, 12, 21, 36, 64, 114, 205, 373, 684, 1262, 2344, 4375, 8202, 15437, 29155, 55236, 104940, 199872, 381551, 729884, 1398878, 2685731, 5164672, 9946439, 19181836, 37039772, 71608456, 138593905, 268520221, 520756816, 1010863710, 1963933206

Offset

1,1

Links

Table of n, a(n) for n=1..36.

Formula

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

Mathematica

z = 50; u = Table[Floor[2^n/(1 - Cos[1/n])], {n, 1, z}]    (* A332430 *)
v = Table[Floor[2^n/(-1 + Cot[1/n])], {n, 1, z}]  (* A332431 *)
u - v   (* A332432 *)
w = Table[Floor[2^n/(1 - Cos[1/n]) - 2^n/(-1 + Cot[1/n])], {n, 1, z}]
u - v - w  (* A332479 *)

Crossrefs

Cf. A333186, A332430, A332432, A332433, A332479.

Sequence in context: A195359 A338303 A316162 * A198840 A211268 A021612

Adjacent sequences: A332428 A332429 A332430 * A332432 A332433 A332434

Keyword

sign,easy

Author

Clark Kimberling, Apr 04 2020

Status

approved