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%I #6 Dec 18 2015 18:18:29
%S 7,102,11538,5336844,22029652542,372027916726176,55925027353114184220,
%T 34340768547284823444042060,187665945665214485110913868661962,
%U 4188970054368199574776535077321295822220
%N 3-loop graph coloring a rectangular array: number of n X n 0..6 arrays where 0..6 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 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph
%C Diagonal of A223247
%H R. H. Hardin, <a href="/A223239/b223239.txt">Table of n, a(n) for n = 1..11</a>
%e Some solutions for n=3
%e ..0..1..0....1..0..6....4..0..6....3..0..5....2..0..1....4..0..5....2..0..4
%e ..1..0..3....0..3..0....0..4..0....0..5..0....0..6..0....0..6..0....0..3..0
%e ..0..3..4....1..0..6....5..0..3....4..0..6....6..0..5....6..0..2....6..0..3
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 18 2013
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