From discordant permutations.

Terms

a(0) =-2a(1) =3a(2) =0a(3) =25a(4) =152a(5) =1350a(6) =12644a(7) =131391a(8) =1489568a(9) =18329481a(10) =243365514a(11) =3468969962a(12) =52848096274a(13) =857073295427