E.g.f. (1+x)^(1+x^2+x^4).

Terms

a(0) =1a(1) =1a(2) =0a(3) =6a(4) =12a(5) =100a(6) =780a(7) =-1092a(8) =43344a(9) =48816a(10) =1264320a(11) =24662880a(12) =-162851040a(13) =4327633440a(14) =-17686783296a(15) =275230488960