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A296583
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Number of nX3 0..1 arrays with each 1 horizontally, vertically or antidiagonally adjacent to 0, 2 or 3 neighboring 1s.
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1
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5, 22, 83, 346, 1465, 6241, 26895, 116541, 507102, 2212212, 9668284, 42302733, 185232946, 811492755, 3556247878, 15588051447, 68336370049, 299606590345, 1313640472782, 5759946595000, 25256394023434, 110746849128771
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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) = 5*a(n-1) +a(n-2) -12*a(n-3) -16*a(n-4) -3*a(n-5) -12*a(n-6) -52*a(n-7) -173*a(n-8) -97*a(n-9) -25*a(n-10) -112*a(n-11) -31*a(n-12) -244*a(n-13) +12*a(n-14) +73*a(n-15) -121*a(n-16) +73*a(n-17) +26*a(n-18) -3*a(n-19) +12*a(n-20) +4*a(n-21)
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EXAMPLE
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Some solutions for n=7
..0..1..0. .1..1..0. .0..0..1. .0..0..1. .1..0..0. .1..0..0. .0..0..0
..1..1..0. .1..0..0. .0..1..1. .0..0..0. .0..0..1. .0..1..0. .0..1..0
..1..0..0. .0..0..0. .0..0..1. .0..1..1. .1..0..0. .1..1..0. .1..1..0
..0..1..1. .0..1..0. .0..1..1. .0..1..0. .0..1..0. .0..0..0. .0..0..0
..0..1..0. .0..0..1. .0..0..0. .0..0..0. .0..0..0. .1..0..0. .1..0..0
..0..1..1. .0..0..0. .1..1..0. .0..1..0. .0..0..0. .0..0..1. .0..0..1
..0..1..1. .0..0..1. .1..1..0. .0..0..0. .1..0..1. .0..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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