A281580 a(n) = binomial(9*n, n-9).

1, 90, 4851, 204156, 7413705, 244222650, 7511839335, 219683466288, 6183023199255, 168899639028120, 4505395859893071, 117891537949758600, 3036500678480436531, 77190387796530738576, 1940723247304668029175, 48339506285032758609456, 1194448077521704400002650

Offset

9,2

Comments

Row 9*n, column n-9 of A007318. - Felix Fröhlich, Feb 05 2017

Links

Table of n, a(n) for n=9..25.

Formula

a(n) ~ 3^(18*n+1) / (2^(24*n+29) * sqrt(Pi*n)). - Amiram Eldar, Sep 17 2025

Mathematica

Table[Binomial[9 n, n - 9], {n, 9, 25}]

Prog

(Magma) [Binomial(9*n, n-9): n in [9..30]];
(PARI) a(n) = binomial(9*n, n-9) \\ Felix Fröhlich, Feb 05 2017

Crossrefs

Cf. sequences with formula binomial(k*n, n-k): A002694 (k=2), A004321 (k=3), A004334 (k=4), A004347 (k=5), A004361 (k=6), A004375 (k=7), A004389 (k=8), this sequence (k=9).

Sequence in context: A221893 A197194 A391617 * A369144 A111599 A111783

Adjacent sequences: A281577 A281578 A281579 * A281581 A281582 A281583

Keyword

nonn,easy

Author

Vincenzo Librandi, Feb 02 2017

Status

approved