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A281467
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Number of nX6 0..1 arrays with no element equal to more than two of its horizontal, diagonal or antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.
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1
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32, 169, 87, 176, 358, 706, 1422, 2858, 5793, 11986, 24812, 51020, 105433, 218415, 451445, 933860, 1933761, 4001344, 8280221, 17142208, 35481002, 73434221, 152010612, 314650743, 651271763, 1348093615, 2790464503, 5775936332
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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) = 2*a(n-1) +3*a(n-3) -4*a(n-4) -4*a(n-5) +a(n-6) -a(n-7) +2*a(n-8) +5*a(n-9) -3*a(n-11) for n>17
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EXAMPLE
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Some solutions for n=4
..0..1..1..0..1..0. .0..0..1..0..1..1. .0..0..1..0..1..1. .0..1..0..1..1..0
..0..1..0..0..1..0. .1..0..1..0..1..0. .1..0..1..0..1..0. .0..1..0..1..0..0
..0..1..0..1..1..0. .1..0..1..0..1..1. .1..0..1..0..1..1. .1..1..0..1..0..1
..1..1..0..1..0..0. .0..0..1..0..0..1. .0..1..0..1..0..0. .1..0..0..1..0..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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