a(n) = (10*n)!*(3*n)!*(n/2)!/((6*n)!*(5*n)!*(3*n/2)!*n!).

A364178

a(n) = (10*n)!*(3*n)!*(n/2)!/((6*n)!*(5*n)!*(3*n/2)!*n!).

Terms

    a(0) =1a(1) =168a(2) =83980a(3) =48664320a(4) =29966636700

External references