A132687 a(n) = binomial(2^n + 3*n - 1, n).

1, 4, 36, 560, 17550, 1370754, 324540216, 267212177232, 822871715492970, 9728874233306696390, 442491588454024774291770, 76919746769405407508866898400, 50743487119356450255156023756871000

Offset

0,2

Links

G. C. Greubel, Table of n, a(n) for n = 0..50

Formula

a(n) = [x^n] 1/(1-x)^(2^n + 2*n).

Mathematica

Table[Binomial[2^n+3n-1, n], {n, 0, 20}] (* Harvey P. Dale, Sep 07 2017 *)

Prog

(PARI) a(n)=binomial(2^n+3*n-1, n)
(Sage) [binomial(2^n +3*n -1, n) for n in (0..20)] # G. C. Greubel, Mar 13 2021
(Magma) [Binomial(2^n +3*n -1, n): n in [0..20]]; // G. C. Greubel, Mar 13 2021

Crossrefs

Sequences of the form binomial(2^n +p*n +q, n): A136556 (0,-1), A014070 (0,0), A136505 (0,1), A136506 (0,2), A060690 (1,-1), A132683 (1,0), A132684 (1,1), A132685 (2,0), A132686 (2,1), this sequence (3,-1), A132688 (3,0), A132689 (3,1).

Cf. A136555.

Sequence in context: A336639 A178184 A070780 * A364152 A238844 A073852

Adjacent sequences: A132684 A132685 A132686 * A132688 A132689 A132690

Keyword

nonn

Author

Paul D. Hanna, Aug 26 2007

Status

approved