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A233177
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Number of 4Xn 0..5 arrays with no element x(i,j) adjacent to itself or value 5-x(i,j) horizontally, diagonally or antidiagonally, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order (unlabelled 6-colorings with no clashing color pairs)
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1
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48, 896, 96256, 7938048, 736362496, 65265467392, 5896922988544, 528589678182400, 47540804020862976, 4269747110598934528, 383704462840431640576, 34473222428763411709952, 3097514921527666217582592
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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Empirical: a(n) = 64*a(n-1) +3328*a(n-2) -77824*a(n-3) -1441792*a(n-4) +28311552*a(n-5) +33554432*a(n-6) -1073741824*a(n-7) for n>8
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EXAMPLE
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Some solutions for n=3
..0..1..5....0..1..0....0..1..2....0..1..2....0..1..2....0..1..2....0..1..0
..5..2..5....0..2..0....3..4..3....2..4..0....3..4..2....5..4..5....5..1..2
..5..3..1....5..2..1....2..1..5....5..1..2....3..1..5....2..1..0....5..4..2
..4..2..0....1..2..1....3..4..2....3..1..2....0..1..3....2..1..3....5..1..5
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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