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A262918
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Number of (4+1) X (n+1) 0..1 arrays with each row divisible by 3 and each column divisible by 7, read as a binary number with top and left being the most significant bits.
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1
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5, 9, 53, 137, 853, 2953, 17333, 71721, 394325, 1791209, 9435253, 44924617, 230950613, 1126125513, 5713545653, 28200027881, 142082597845, 705663892009, 3542422689653, 17650591452297, 88436516562773, 441384307595273
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OFFSET
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1,1
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LINKS
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FORMULA
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Empirical: a(n) = 7*a(n-1) + 11*a(n-2) - 147*a(n-3) + 99*a(n-4) + 777*a(n-5) - 1019*a(n-6) - 637*a(n-7) + 910*a(n-8).
Empirical g.f.: x*(5 - 26*x - 65*x^2 + 402*x^3 + 139*x^4 - 1510*x^5 + 273*x^6 + 910*x^7) / ((1 - x)*(1 + x)*(1 - 2*x)*(1 - 5*x)*(1 - 7*x^2)*(1 - 13*x^2)). - Colin Barker, Jan 01 2019
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EXAMPLE
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Some solutions for n=4:
..0..0..0..0..0....1..1..0..0..0....0..0..0..0..0....0..0..0..1..1
..0..1..1..1..1....0..0..0..1..1....0..1..1..0..0....0..0..0..1..1
..0..1..1..1..1....1..1..0..1..1....0..1..1..0..0....1..1..0..1..1
..0..1..1..1..1....0..0..0..1..1....0..1..1..0..0....1..1..0..0..0
..0..0..0..0..0....1..1..0..0..0....0..0..0..0..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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