OFFSET
0,2
FORMULA
a(n)=Sum_{k=0..n} C(n+(n-k)*k, (n-k)*k+k).
PROG
(PARI) a(n)=sum(k=0, n, binomial(n+(n-k)*k, (n-k)*k+k))
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, May 31 2005
STATUS
approved