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A297722
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Number of 3Xn 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1, 2 or 4 neighboring 1s.
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1
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1, 29, 145, 523, 2717, 14462, 68919, 332306, 1652441, 8140067, 39816114, 195543171, 961617387, 4722204339, 23186542778, 113898106759, 559470061363, 2747805117373, 13496167444555, 66289849507630, 325594360281088
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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) = 6*a(n-1) -5*a(n-2) +6*a(n-3) -17*a(n-4) -168*a(n-5) +284*a(n-6) +316*a(n-7) -636*a(n-8) +40*a(n-9) +732*a(n-10) -863*a(n-11) -414*a(n-12) +846*a(n-13) +17*a(n-14) -297*a(n-15) +188*a(n-16) +50*a(n-17) -52*a(n-18)
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EXAMPLE
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Some solutions for n=7
..0..1..0..0..0..0..0. .0..0..0..1..0..1..0. .1..0..1..1..1..1..1
..0..1..1..0..1..1..0. .0..0..0..0..1..0..1. .1..1..0..0..0..0..0
..0..0..0..0..0..0..0. .0..0..0..0..0..0..0. .1..1..0..0..1..1..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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