a(n) = (7*n)!*(6*n)!*(2*n)! / ((4*n)!^2 * (3*n)!^2 * n!).

A364508

a(n) = (7*n)!*(6*n)!*(2*n)! / ((4*n)!^2 * (3*n)!^2 * n!).

Terms

    a(0) =1a(1) =350a(2) =594594a(3) =1299170600

External references