a(n) = binomial(n, floor(n/2))*FallingFactorial(n - 1, n - floor(n/2)).

A343581

a(n) = binomial(n, floor(n/2))*FallingFactorial(n - 1, n - floor(n/2)).

Terms

    a(0) =1a(1) =0a(2) =2a(3) =6a(4) =36a(5) =240a(6) =1200a(7) =12600a(8) =58800a(9) =846720a(10) =3810240a(11) =69854400a(12) =307359360a(13) =6849722880a(14) =29682132480a(15) =779155977600

External references