(n-1)-st elementary symmetric function of the first n terms of (1,2,6,20,70,252,...)=A000984.

A203194

(n-1)-st elementary symmetric function of the first n terms of (1,2,6,20,70,252,...)=A000984.

Terms

    a(0) =1a(1) =3a(2) =20a(3) =412a(4) =29080a(5) =7344960a(6) =6790976640

External references