OFFSET
0,2
FORMULA
(empirical) set p,q,r to n,7,6 (in any order) in s=p+q+r-1; a(n) = product {i in 0..r-1} (binomial(s,p+i)*i!/(s-i)^(r-i-1))
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jul 05 2008
STATUS
approved