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A188865
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Number of n X 8 binary arrays without the pattern 0 1 diagonally, vertically or antidiagonally.
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2
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256, 1393, 3194, 5275, 7442, 9627, 11814, 14001, 16188, 18375, 20562, 22749, 24936, 27123, 29310, 31497, 33684, 35871, 38058, 40245, 42432, 44619, 46806, 48993, 51180, 53367, 55554, 57741, 59928, 62115, 64302, 66489, 68676, 70863, 73050, 75237, 77424
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OFFSET
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1,1
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COMMENTS
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Column 8 of A188866.
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LINKS
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R. H. Hardin, Table of n, a(n) for n = 1..200
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FORMULA
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Empirical: a(n) = 2187*n - 3495 for n>5.
Conjectures from Colin Barker, Feb 28 2018: (Start)
G.f.: x*(256 + 881*x + 664*x^2 + 280*x^3 + 86*x^4 + 18*x^5 + 2*x^6) / (1 - x)^2.
a(n) = 2*a(n-1) - a(n-2) for n>7.
(End)
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EXAMPLE
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Some solutions for 3 X 8:
..1..1..1..1..1..1..1..1....1..1..1..1..1..1..1..1....1..1..0..1..1..1..1..1
..1..1..1..1..1..1..1..1....1..1..1..1..1..1..1..1....0..0..0..0..1..1..1..1
..0..0..0..0..1..1..1..0....0..0..1..0..1..1..1..0....0..0..0..0..0..0..0..0
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CROSSREFS
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Cf. A188866.
Sequence in context: A206320 A237315 A237309 * A187964 A187956 A237225
Adjacent sequences: A188862 A188863 A188864 * A188866 A188867 A188868
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KEYWORD
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nonn
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AUTHOR
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R. H. Hardin, Apr 12 2011
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STATUS
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approved
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