A234506 a(n) = binomial(9*n+3, n)/(3*n+1).

1, 3, 30, 406, 6327, 107019, 1909908, 35399520, 674842149, 13147742322, 260626484118, 5239783981320, 106585537781775, 2189670831627678, 45366284782209600, 946815917066740800, 19887218367823853937, 420076689292591271325, 8917736795123409615060, 190161017612160607167948, 4071301730663135449185705

Offset

0,2

Comments

Fuss-Catalan sequence is a(n,p,r) = r*binomial(n*p + r, n)/(n*p + r), where p=9, r=3.

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..200

J-C. Aval, Multivariate Fuss-Catalan Numbers, arXiv:0711.0906v1, Discrete Math., 308 (2008), 4660-4669.

Thomas A. Dowling, Catalan Numbers Chapter 7

Wojciech Mlotkowski, Fuss-Catalan Numbers in Noncommutative Probability, Docum. Mathm. 15: 939-955.

Formula

G.f. satisfies: B(x) = {1 + x*B(x)^(p/r)}^r, where p=9, r=3.

Mathematica

Table[Binomial[9n+3, n]/(3n+1), {n, 0, 30}]

Prog

(PARI) a(n) = binomial(9*n+3, n)/(3*n+1);
(PARI) {a(n)=local(B=1); for(i=0, n, B=(1+x*B^3)^3+x*O(x^n)); polcoeff(B, n)}
(Magma) [Binomial(9*n+3, n)/(3*n+1): n in [0..30]];
(Sage) [binomial(9*n+3, n)/(3*n+1) for n in (0..30)] # G. C. Greubel, Feb 09 2021

Crossrefs

Cf. A000108, A143554, A232265, A234505, A234507, A234508, A234509, A234510, A234513.

Sequence in context: A372110 A354659 A058831 * A212425 A336538 A294240

Adjacent sequences: A234503 A234504 A234505 * A234507 A234508 A234509

Keyword

nonn

Author

Tim Fulford, Dec 27 2013

Status

approved