A295471 a(n) = (20*n)!*n!/((10*n)!*(8*n)!*(3*n)!).

1, 2771340, 44524428808860, 835982760936614190900, 16702642470437308383606668060, 345116202503279265243707597937393840, 7282855378270617096441349556073829143864900, 155927544469969434644890704895476696960247603510200

Offset

0,2

Links

Table of n, a(n) for n=0..7.

Formula

G.f.: hypergeom([1/20, 3/20, 7/20, 9/20, 11/20, 13/20, 17/20, 19/20], [1/8, 1/3, 3/8, 1/2, 5/8, 2/3, 7/8], 625000000/27*x).

Mathematica

Table[((20n)!n!)/((10n)!(8n)!(3n)!), {n, 0, 10}] (* Harvey P. Dale, Feb 03 2021 *)

Crossrefs

Cf. A295431.

Sequence in context: A306634 A015336 A251835 * A316487 A250535 A203912

Adjacent sequences: A295468 A295469 A295470 * A295472 A295473 A295474

Keyword

nonn

Author

Gheorghe Coserea, Nov 28 2017

Status

approved