A100009 a(1) = 2; for n >= 2, a(n) = f(a(n-1)) where f(n) = n*(n+1)*(n+2)*(n+3)/24.

2, 5, 70, 1088430, 58478088289964410654020

Offset

1,1

Comments

The next term has 90 digits.

Links

Table of n, a(n) for n=1..5.

Mathematica

NestList[(6 #+11 #^2+6 #^3+#^4)/24&, 2, 6] (* Harvey P. Dale, Dec 14 2024 *)

Crossrefs

Cf. A000332.

Sequence in context: A375973 A066933 A132496 * A167218 A013045 A290864

Adjacent sequences: A100006 A100007 A100008 * A100010 A100011 A100012

Keyword

easy,nonn,less

Author

Jonathan Vos Post, Nov 16 2004

Status

approved