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A228503
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Number of nX5 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically, diagonally or antidiagonally.
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1
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5, 11, 88, 358, 2002, 9528, 49101, 243118, 1228036, 6141239, 30865981, 154742849, 776765183, 3896668986, 19553995645, 98108834263, 492283814664, 2470048647138, 12393793010466, 62186850336292, 312029099308093, 1565635002686314
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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) +16*a(n-2) +a(n-3) -27*a(n-4) +a(n-5) +4*a(n-6).
Empirical: g.f. -x*(5+x-14*x^2+x^3+2*x^4) / ( -1+2*x+16*x^2+x^3-27*x^4+x^5+4*x^6 ). - R. J. Mathar, Aug 25 2013
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EXAMPLE
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Some solutions for n=4
..1..0..0..0..0....1..0..0..0..0....1..0..0..0..0....1..0..0..0..1
..0..0..0..1..0....0..0..1..0..1....0..0..0..0..0....0..0..0..0..0
..0..0..0..0..0....1..0..0..0..0....0..1..0..0..1....1..0..0..0..0
..0..0..0..0..1....0..0..0..1..0....0..0..0..0..0....0..0..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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