a(n) = Sum_{j=1..n-1} j*(n-j)*b^(j-1) with b = floor(n^2/4)+1.
A211869
a(n) = Sum_{j=1..n-1} j*(n-j)*b^(j-1) with b = floor(n^2/4)+1.
Terms
- a(0) =0a(1) =1a(2) =8a(3) =98a(4) =1712a(5) =58985a(6) =2541896a(7) =187337236a(8) =15687030920
External references
- oeis: A211869