a(n) = Sum_{k=1..n+1} (-1)^(k-1) k (n - k + 1)!.
A374651
a(n) = Sum_{k=1..n+1} (-1)^(k-1) k (n - k + 1)!.
Terms
- a(0) =-1a(1) =3a(2) =1a(3) =19a(4) =81a(5) =539a(6) =3881a(7) =32019a(8) =294961a(9) =3006859a(10) =33608121a(11) =408778499a(12) =5375855681a(13) =76017801339
External references
- oeis: A374651