A288967 Number of (undirected) paths on the n X n rook graph.
0, 12, 4536, 111933456
Offset: 1
Links
- Eric Weisstein's World of Mathematics, Graph Path
- Eric Weisstein's World of Mathematics, Rook Graph
This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
a(n)={sum(k=2, n, binomial(n,k)*k!) + sum(k=1, n, k*binomial(n,k)*binomial(k-1,k\2)*sum(i=0, n-k, binomial(n-k,i)*(k\2+i)!)*sum(i=0, n-k, binomial(n-k,i)*((k-1)\2+i)!))} \\ Andrew Howroyd, May 28 2025