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

A383704

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

Terms

    a(0) =1a(1) =2a(2) =-34a(3) =-540a(4) =26614a(5) =805980a(6) =-66399124a(7) =-2972817848a(8) =343902030758

External references