# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a223289 Showing 1-1 of 1 %I A223289 #8 Mar 15 2023 11:08:19 %S A223289 9,168,42168,46008720,757664837832,53263771547091072, %T A223289 56395315109321439563328,254765586321230138822186989968, %U A223289 17333186258617759005034608109179216168 %N A223289 4-loop graph coloring a rectangular array: number of n X n 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. %C A223289 Diagonal of A223297. %H A223289 R. H. Hardin, Table of n, a(n) for n = 1..10 %e A223289 Some solutions for 3 X 3 %e A223289 ..0..1..0..5....0..3..0..7....0..3..0..3....0..3..0..6....1..0..8..0 %e A223289 ..2..0..1..0....3..0..6..0....2..0..8..0....2..0..2..0....0..3..0..5 %e A223289 ..0..6..0..1....0..2..0..6....0..1..0..1....0..8..0..1....4..0..4..0 %Y A223289 Cf. A223297. %K A223289 nonn %O A223289 1,1 %A A223289 _R. H. Hardin_, Mar 19 2013 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE