A372990 a(n) = floor((3n)!/(n!^3 a(n-1)), where a(0)=1.

1, 6, 15, 112, 309, 2449, 7004, 56977, 166128, 1371673, 4046880, 33736358, 100328902, 842011587, 2518460195, 21241145637, 63807550099, 540215987658, 1628274148825, 13827134974963, 41789656029594, 355743023641567, 1077551461258952, 9191485155260759

Offset

0,2

Links

Table of n, a(n) for n=0..23.

Mathematica

a[0] = 1; a[n_] := a[n] = Floor[(3 n)!/( (n!)^3*a[n - 1])];
Table[a[n], {n, 0, 30}]

Crossrefs

Cf. A372989.

Sequence in context: A013228 A133472 A213873 * A219771 A087137 A056317

Adjacent sequences: A372987 A372988 A372989 * A372991 A372992 A372993

Keyword

nonn

Author

Clark Kimberling, Jul 15 2024

Status

approved