a(n) = (1/(n+1)) * Sum_{k=0..n} binomial(n+k,k) * binomial(n*(n+1),n-k) * n^k.
A366038
a(n) = (1/(n+1)) * Sum_{k=0..n} binomial(n+k,k) * binomial(n*(n+1),n-k) * n^k.
Terms
- a(0) =1a(1) =2a(2) =25a(3) =658a(4) =27193a(5) =1548526a(6) =112916830a(7) =10062563610
External references
- oeis: A366038