a(n) = floor(n/2)-th elementary symmetric function of C(n,0), C(n,1), ..., C(n, floor(n/2)).
A025140
a(n) = floor(n/2)-th elementary symmetric function of C(n,0), C(n,1), ..., C(n, floor(n/2)).
Terms
- a(0) =1a(1) =1a(2) =3a(3) =4a(4) =34a(5) =65a(6) =2310a(7) =6272a(8) =1047424a(9) =3973536a(10) =3255714000a(11) =17050908600
External references
- oeis: A025140