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A317763
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Number of nX7 0..1 arrays with every element unequal to 0, 1 or 2 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
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1
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64, 190, 196, 232, 302, 425, 639, 1012, 1663, 2801, 4792, 8278, 14385, 25088, 43852, 76756, 134466, 235697, 413288, 724863, 1271539, 2230756, 3913889, 6867349, 12050002, 21144516, 37103735, 65109496, 114255232, 200498730, 351843854
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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) = 3*a(n-1) -2*a(n-2) -a(n-4) +a(n-5) -a(n-6) +a(n-7) for n>11
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EXAMPLE
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Some solutions for n=5
..0..1..1..1..1..0..0. .0..0..0..1..0..0..0. .0..0..0..0..1..1..1
..1..1..1..1..0..0..0. .0..0..1..1..0..0..0. .0..0..0..1..1..1..1
..1..1..1..0..0..0..0. .0..1..1..1..0..0..0. .0..0..1..1..1..1..0
..1..1..0..0..0..0..1. .1..1..1..1..0..0..1. .0..1..1..1..1..0..0
..1..0..0..0..0..1..1. .1..1..1..1..0..1..1. .1..1..1..1..0..0..0
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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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