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A228680
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Number of n X 5 binary arrays with no two ones adjacent horizontally, diagonally or antidiagonally.
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1
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13, 97, 809, 6737, 56549, 475809, 4008817, 33795201, 284980061, 2403420097, 20270798553, 170971640209, 1442058561397, 12163101107393, 102590452275041, 865306832676993, 7298499493581101, 61559793235182241, 519231197740651273
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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) = 12*a(n-1) -27*a(n-2) -32*a(n-3) +49*a(n-4) +20*a(n-5) -5*a(n-6).
Empirical g.f.: -x*(-13+59*x+4*x^2-64*x^3-15*x^4+5*x^5) / ( 1-12*x+27*x^2+32*x^3-49*x^4-20*x^5+5*x^6 ). - R. J. Mathar, Sep 02 2013
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EXAMPLE
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Some solutions for n=4:
..0..0..1..0..0....0..0..0..0..0....0..0..1..0..0....0..1..0..0..1
..0..0..0..0..1....0..0..1..0..1....0..0..0..0..1....0..0..0..0..1
..1..0..0..0..0....0..0..0..0..0....1..0..0..0..1....0..0..0..0..1
..0..0..1..0..0....0..0..0..0..1....0..0..0..0..0....1..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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