a(n) = [x^n] Product_{k=0..n} (1 + (2*n+k)*x).

A383678

a(n) = [x^n] Product_{k=0..n} (1 + (2*n+k)*x).

Terms

    a(0) =1a(1) =5a(2) =74a(3) =1650a(4) =48504a(5) =1763100a(6) =76223664a(7) =3817038960a(8) =217177416576

External references