OFFSET
0,2
FORMULA
a(n) = Sum_{k=0..n} binomial(n+7*k/2,n-k) * binomial(9*k/2,k) / (7*k/2+1).
PROG
(PARI) a(n) = sum(k=0, n, binomial(n+7*k/2, n-k)*binomial(9*k/2, k)/(7*k/2+1));
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Oct 09 2023
STATUS
approved