a(n) = (1/2)*(3rd elementary symmetric function of C(n,0), C(n,1), ..., C(n,[ n/2 ])).

A025138

a(n) = (1/2)*(3rd elementary symmetric function of C(n,0), C(n,1), ..., C(n,[ n/2 ])).

Terms

    a(0) =12a(1) =25a(2) =1155a(3) =3136a(4) =89012a(5) =282339a(6) =6356460a(7) =22384516a(8) =437787537a(9) =1663878008a(10) =29545748596a(11) =119083774720

External references