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A228480
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Number of nX6 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or antidiagonally.
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1
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8, 41, 386, 3084, 25699, 211588, 1748684, 14433982, 119188751, 984088952, 8125411159, 67089476825, 553940891394, 4573752281524, 37764327367307, 311810620896975, 2574542371273857, 21257353083201847, 175516652771106311
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OFFSET
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1,1
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COMMENTS
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Same recurrences as A228285 except in addition a smaller one for column 5
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LINKS
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FORMULA
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a(n) = a(n-1) +42*a(n-2) +147*a(n-3) +70*a(n-4) -478*a(n-5) -449*a(n-6) +1199*a(n-7) +732*a(n-8) -2727*a(n-9) +659*a(n-10) +3827*a(n-11) -5776*a(n-12) +3926*a(n-13) -1152*a(n-14) -148*a(n-15) +154*a(n-16) +32*a(n-17) -29*a(n-18) -6*a(n-19) +3*a(n-20) +a(n-21)
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EXAMPLE
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Some solutions for n=4
..1..0..0..0..0..0....1..0..0..0..0..1....1..0..0..1..0..0....1..0..1..0..0..0
..0..1..0..0..0..1....0..0..0..0..0..0....0..1..0..0..0..0....0..0..0..1..0..0
..0..0..0..1..0..0....1..0..1..0..0..0....0..0..0..0..0..1....0..1..0..0..0..1
..0..0..0..0..0..1....0..0..0..0..0..1....0..1..0..1..0..0....0..0..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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