OFFSET
0,2
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..737 (first 50 terms from Christian N. Hofmann)
FORMULA
a(n) = Sum_{k=0..n} binomial(n,k) * binomial(3*n+3*k+1,n)/(3*n+3*k+1).
MAPLE
a:= n-> sum(binomial(n, k)*binomial(3*n+3*k+1, n)/(3*n+3*k+1), k=0..n):
seq(a(n), n=0..49); # Christian N. Hofmann, Jul 14 2023
PROG
(PARI) a(n) = sum(k=0, n, binomial(n, k)*binomial(3*n+3*k+1, n)/(3*n+3*k+1));
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Seiichi Manyama, Jul 13 2023
STATUS
approved