4-loop graph coloring a rectangular array: number of n X 1 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.

A223290

4-loop graph coloring a rectangular array: number of n X 1 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) =9a(1) =24a(2) =96a(3) =288a(4) =1056a(5) =3360a(6) =11808a(7) =38688a(8) =133152a(9) =442656a(10) =1507872a(11) =5049120a(12) =17112096a(13) =57505056a(14) =194401824a(15) =654442272a(16) =2209656864a(17) =7445195040a(18) =25122449952a(19) =84684010272a(20) =285663609888a(21) =963135692064

External references