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A303017
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Number of 3 X n 0..1 arrays with every element equal to 0, 1, 2, 4 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
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1
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4, 25, 68, 187, 579, 1797, 5571, 17382, 54589, 171758, 541502, 1710237, 5408966, 17123725, 54254138, 172005475, 545590319, 1731242563, 5495164970, 17446421788, 55400350112, 175946894177, 558856114250, 1775239587936, 5639545671984, 17916569853876, 56922515406874
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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) = 6*a(n-1) -7*a(n-2) -11*a(n-3) +11*a(n-4) +a(n-5) +49*a(n-6) -12*a(n-7) -59*a(n-8) -61*a(n-9) +23*a(n-10) +89*a(n-11) +28*a(n-12) -24*a(n-13) -44*a(n-14) +12*a(n-15) for n>16.
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EXAMPLE
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Some solutions for n=5:
..0..1..0..1..1. .0..0..0..1..1. .0..0..1..1..1. .0..0..1..1..1
..1..1..0..1..0. .0..1..0..0..1. .1..0..0..1..0. .1..0..1..0..1
..1..0..0..0..0. .1..1..0..1..0. .1..0..1..0..1. .1..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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