a(n) = [x^(2*n)] Product_{k=0..n-1} (1 + k*x)^3.

A384026

a(n) = [x^(2*n)] Product_{k=0..n-1} (1 + k*x)^3.

Terms

    a(0) =1a(1) =0a(2) =0a(3) =8a(4) =1188a(5) =240480a(6) =68630824a(7) =26730127872

External references