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%I #4 Mar 19 2013 08:47:52
%S 1056,93528,22346136,2997483624,757664837832,101979342907800,
%T 25787363600621016,3471044597151840072,877705282143571802568,
%U 118143428663004983310744,29873806714316160766516056
%N 4-loop graph coloring a rectangular array: number of nX5 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 Column 5 of A223297
%H R. H. Hardin, <a href="/A223294/b223294.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 11*a(n-1) +34195*a(n-2) -375378*a(n-3) -5432170*a(n-4) +39355259*a(n-5) +159772183*a(n-6) -813855390*a(n-7) -1806659599*a(n-8) +5426882284*a(n-9) +8483799904*a(n-10) -12122996938*a(n-11) -14048837612*a(n-12) +6003447012*a(n-13) +4824541120*a(n-14) -380459520*a(n-15) -157351936*a(n-16)
%e Some solutions for n=3
%e ..0..1..0..3..0....0..1..0..3..0....0..1..0..2..0....0..1..0..4..0
%e ..1..0..2..0..2....1..0..1..0..6....1..0..2..0..6....1..2..1..0..1
%e ..0..2..0..8..0....0..5..0..3..0....0..1..0..2..0....0..1..0..6..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 19 2013
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