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A227640
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Number of nX5 0,1 arrays indicating 2X2 subblocks of some larger (n+1)X6 binary array having determinant equal to one, with rows and columns of the latter in nondecreasing lexicographic order
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1
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5, 44, 377, 3202, 25241, 179234, 1147095, 6679750, 35730988, 177168580, 820755334, 3576675995, 14747597428, 57825369396, 216544923909, 777378404391, 2683990390975, 8937664937815, 28776814807337, 89782546245762
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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 polynomial of degree 39 (see link above)
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EXAMPLE
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Some solutions for n=4
..0..0..1..0..0....0..0..0..0..1....0..0..0..1..0....0..0..1..0..0
..0..1..0..0..0....0..1..0..0..0....0..0..0..0..0....0..1..0..0..1
..0..1..0..0..0....1..0..0..1..0....0..1..1..0..0....0..0..0..0..0
..1..0..1..0..1....0..0..0..0..0....1..0..1..1..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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