a(n) = (10*n)!*(n/2)!/((5*n)!*(7*n/2)!*(2*n)!).

A364180

a(n) = (10*n)!*(n/2)!/((5*n)!*(7*n/2)!*(2*n)!).

Terms

    a(0) =1a(1) =1152a(2) =5542680a(3) =31473008640

External references