a(n) = Sum_{k=0..floor(n/2)} binomial(n-k,k)^n * n/(n-k).
A181083
a(n) = Sum_{k=0..floor(n/2)} binomial(n-k,k)^n * n/(n-k).
Terms
- a(0) =1a(1) =3a(2) =13a(3) =111a(4) =1686a(5) =88737a(6) =14355265a(7) =3583775847
External references
- oeis: A181083
A181083
a(n) = Sum_{k=0..floor(n/2)} binomial(n-k,k)^n * n/(n-k).