OFFSET
0,2
PROG
(PARI) a(n) = sum(k=0, n, binomial(n, k)*binomial(3*n/2+3*k/2+1, n)/(3*n/2+3*k/2+1));
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Mar 31 2024
STATUS
editing