a(n) = A361540(n,2) for n >= 2, a column of triangle A361540.
A361549
a(n) = A361540(n,2) for n >= 2, a column of triangle A361540.
Terms
- a(0) =1a(1) =18a(2) =426a(3) =12040a(4) =401355a(5) =15456756a(6) =676130644a(7) =33151425840
External references
- oeis: A361549