a(n) = (9*n)!*n!/((5*n)!*(3*n)!*(2*n)!).

A295441

a(n) = (9*n)!*n!/((5*n)!*(3*n)!*(2*n)!).

Terms

    a(0) =1a(1) =252a(2) =204204a(3) =191222460a(4) =190004674860

External references