a(n) = (n!)^2 * Sum_{k=0..n} (-1)^(n-k) * (k+1) / ((n-k)!)^2.
A337151
a(n) = (n!)^2 * Sum_{k=0..n} (-1)^(n-k) * (k+1) / ((n-k)!)^2.
Terms
- a(0) =1a(1) =1a(2) =5a(3) =53a(4) =977a(5) =27649a(6) =1111429a(7) =60147205a(8) =4213400897a(9) =370767834593
External references
- oeis: A337151