4-loop graph coloring a rectangular array: number of n X 3 0..8 arrays where 0..8 label nodes of a graph with edges 0,1 1,2 2,0 0,3 3,4 4,0 0,5 5,6 6,0 0,7 7,8 8,0 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph.

A223292

4-loop graph coloring a rectangular array: number of n X 3 0..8 arrays where 0..8 label nodes of a graph with edges 0,1 1,2 2,0 0,3 3,4 4,0 0,5 5,6 6,0 0,7 7,8 8,0 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph.

Terms

    a(0) =96a(1) =1368a(2) =42168a(3) =709320a(4) =22346136a(5) =377262504a(6) =11864385048a(7) =200704309992

External references