a(n) = n! * Sum_{k=0..n} (-k)^(n-k) * (n-k)^k/k!.

A351780

a(n) = n! * Sum_{k=0..n} (-k)^(n-k) * (n-k)^k/k!.

Terms

    a(0) =1a(1) =0a(2) =-2a(3) =6a(4) =108a(5) =-2420a(6) =8730a(7) =1313718a(8) =-57930152a(9) =567983736a(10) =109544982390

External references