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A232918
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Number of nX6 0..2 arrays with no element x(i,j) adjacent to value 2-x(i,j) horizontally, diagonally or antidiagonally
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1
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96, 1080, 13992, 186720, 2515716, 33994188, 459797904, 6221092260, 84180552504, 1139126465856, 15414771639624, 208595002222596, 2822742415594800, 38197837835124312, 516899809502860032, 6994778773839006000
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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) = 18*a(n-1) -56*a(n-2) -81*a(n-3) +280*a(n-4) +12*a(n-5) -259*a(n-6) +78*a(n-7) +24*a(n-8) -5*a(n-9)
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EXAMPLE
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Some solutions for n=3
..1..2..2..1..2..1....2..2..1..2..1..0....0..0..0..0..0..1....2..1..0..1..0..1
..2..2..2..2..2..2....2..2..1..2..1..2....0..0..0..1..0..0....0..1..2..1..2..1
..2..2..1..2..2..1....2..2..1..0..1..2....1..0..0..0..0..0....2..1..2..2..2..1
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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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