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A302455
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Number of nX3 0..1 arrays with every element equal to 0, 2, 3 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
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1
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1, 11, 18, 55, 177, 474, 1397, 4135, 11882, 34847, 101857, 296482, 867237, 2532855, 7392050, 21600199, 63090609, 184246522, 538224973, 1572126423, 4591906058, 13413050687, 39179099921, 114439818402, 334276528661, 976412435063
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OFFSET
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1,2
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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) +13*a(n-3) -23*a(n-4) +12*a(n-5) -42*a(n-6) +32*a(n-7) -24*a(n-8) -18*a(n-9) +24*a(n-10) +40*a(n-11) +32*a(n-12)
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EXAMPLE
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Some solutions for n=5
..0..0..1. .0..0..0. .0..0..0. .0..1..0. .0..0..0. .0..0..1. .0..1..1
..1..0..0. .1..0..1. .1..0..1. .1..1..1. .0..0..1. .0..0..0. .0..1..1
..1..0..1. .1..0..0. .1..0..1. .0..1..1. .1..0..1. .1..0..1. .0..1..1
..0..0..1. .0..0..0. .0..0..0. .1..1..1. .0..0..0. .1..0..1. .1..1..0
..0..0..1. .1..0..1. .0..0..1. .0..1..0. .1..0..0. .0..0..0. .1..1..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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