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4X4X4 triangular graph coloring a rectangular array: number of n X n 0..9 arrays where 0..9 label nodes of a graph with edges 0,1 0,2 1,2 1,3 1,4 2,4 3,4 2,5 4,5 3,6 3,7 4,7 6,7 4,8 5,8 7,8 5,9 8,9 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph
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%I #5 Dec 18 2015 18:18:30

%S 10,324,76788,118001928,1208825525124,82235766550254744,

%T 37878775658906097327552,117618648410211422628657954648,

%U 2498412967821017756764735962549014076

%N 4X4X4 triangular graph coloring a rectangular array: number of n X n 0..9 arrays where 0..9 label nodes of a graph with edges 0,1 0,2 1,2 1,3 1,4 2,4 3,4 2,5 4,5 3,6 3,7 4,7 6,7 4,8 5,8 7,8 5,9 8,9 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph

%C Diagonal of A223305

%e Some solutions for n=3

%e ..2..5..8....1..2..4....4..1..3....7..8..4....4..7..3....8..7..6....8..4..8

%e ..0..2..4....2..4..7....1..2..4....3..4..1....5..8..4....7..6..7....4..2..4

%e ..2..0..1....4..1..4....0..1..2....4..2..4....9..5..2....4..3..6....5..4..1

%K nonn

%O 1,1

%A _R. H. Hardin_ Mar 19 2013