a(n) = Sum_{k=0..n} C(n,k)^2*(n-k)!*k^3.
A105218
a(n) = Sum_{k=0..n} C(n,k)^2*(n-k)!*k^3.
Terms
- a(0) =0a(1) =1a(2) =12a(3) =117a(4) =1168a(5) =12525a(6) =145836a(7) =1844017a(8) =25238592a(9) =372320793a(10) =5894109100a(11) =99712850061
External references
- oeis: A105218