a(n) = Product_{k=0..n-1} (3*n+k-1).

A384263

a(n) = Product_{k=0..n-1} (3*n+k-1).

Terms

    a(0) =1a(1) =2a(2) =30a(3) =720a(4) =24024a(5) =1028160a(6) =53721360a(7) =3315312000a(8) =235989936000

External references