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A206983
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Number of nX4 0..1 arrays avoiding the patterns 0 1 0 or 1 0 1 in any row, column, diagonal or antidiagonal
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1
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10, 100, 158, 556, 1866, 5804, 18528, 59888, 191484, 612874, 1966402, 6301118, 20187672, 64705162, 207369486, 664535672, 2129687696, 6825166670, 21872797724, 70096742330, 224642588748, 719921959060, 2307166259316, 7393882758084
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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) = 4*a(n-1) -4*a(n-2) +10*a(n-3) -18*a(n-4) +8*a(n-5) -16*a(n-6) -4*a(n-7) -3*a(n-8) +21*a(n-9) +13*a(n-10) -12*a(n-11) for n>13
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EXAMPLE
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Some solutions for n=4
..1..0..0..1....1..1..1..1....0..0..1..1....1..1..1..0....1..1..1..1
..0..0..0..1....1..1..1..1....1..1..1..1....0..1..1..0....0..1..1..1
..0..0..0..0....1..1..1..0....1..1..1..1....0..1..1..1....0..1..1..1
..1..0..0..0....1..0..0..0....0..0..0..0....1..1..1..1....1..1..1..1
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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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