a(n) = n! * Sum_{k=0..floor(n/2)} (n - 2*k)^n/(n - 2*k)!.
A356834
a(n) = n! * Sum_{k=0..floor(n/2)} (n - 2*k)^n/(n - 2*k)!.
Terms
- a(0) =1a(1) =1a(2) =4a(3) =33a(4) =448a(5) =8105a(6) =192576a(7) =5946913a(8) =226097152a(9) =10389920913a(10) =571788928000
External references
- oeis: A356834