a(n) = (20*n)!*(9*n)!*(6*n)!/((18*n)!*(10*n)!*(4*n)!*(3*n)!).

A295476

a(n) = (20*n)!*(9*n)!*(6*n)!/((18*n)!*(10*n)!*(4*n)!*(3*n)!).

Terms

    a(0) =1a(1) =190a(2) =95238a(3) =54503020a(4) =32989143110

External references