a(n) = 0!*1!*2!*(3*n)!*3*n*(n-1) / ((n)!*(n+1)!*(n+2)!).

A181201

a(n) = 0!*1!*2!*(3*n)!*3*n*(n-1) / ((n)!*(n+1)!*(n+2)!).

Terms

    a(0) =0a(1) =30a(2) =756a(3) =16632a(4) =360360a(5) =7876440a(6) =174594420a(7) =3926434512a(8) =89492111280

External references