A132688 a(n) = binomial(2^n + 3*n, n).

1, 5, 45, 680, 20475, 1533939, 350161812, 280384608504, 847073824772175, 9894081531608130857, 446730013630787463700695, 77328499046923986969058944720, 50891283683781760304442885961988100

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 + 1).

Mathematica

Table[Binomial[2^n+3n, n], {n, 0, 20}] (* Harvey P. Dale, Oct 30 2018 *)

Prog

(PARI) a(n)=binomial(2^n+3*n, n)
(Sage) [binomial(2^n +3*n, n) for n in (0..20)] # G. C. Greubel, Mar 13 2021
(Magma) [Binomial(2^n +3*n, 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), A132687 (3,-1), this sequence (3,0), A132689 (3,1).

Cf. A136555.

Sequence in context: A085356 A113382 A304919 * A295227 A167812 A155104

Adjacent sequences: A132685 A132686 A132687 * A132689 A132690 A132691

Keyword

nonn

Author

Paul D. Hanna, Aug 26 2007

Status

approved