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A281404
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Number of 5 X n 0..1 arrays with no element equal to more than two of its horizontal, diagonal or antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.
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1
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0, 160, 1413, 2886, 5892, 10130, 16241, 25680, 41353, 67226, 108849, 176500, 287083, 467706, 762549, 1242828, 2024499, 3295966, 5361623, 8713840, 14148393, 22950214, 37193019, 60220156, 97418383, 157461854, 254309175, 410409716, 661848005
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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) = 4*a(n-1) -6*a(n-2) +6*a(n-3) -7*a(n-4) +8*a(n-5) -9*a(n-6) +8*a(n-7) -5*a(n-8) +4*a(n-9) -3*a(n-10) +2*a(n-11) -a(n-12) for n>19.
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EXAMPLE
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Some solutions for n=4
..0..1..1..0. .0..1..0..1. .0..1..1..0. .0..0..0..1. .0..1..1..0
..0..1..0..0. .0..1..0..0. .0..1..0..0. .0..1..0..1. .1..0..1..0
..1..1..0..1. .0..1..1..1. .0..1..0..1. .0..1..0..1. .0..0..1..1
..0..0..0..1. .0..1..0..1. .1..1..1..0. .1..1..0..1. .1..1..0..0
..0..1..1..0. .0..1..0..0. .0..0..0..1. .1..0..0..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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