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A240651
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Number of nX3 0..1 arrays with no element equal to exactly one horizontal or vertical neighbor, with new values 0..1 introduced in row major order
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1
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1, 2, 9, 17, 43, 136, 402, 1180, 3518, 10525, 31454, 94059, 281484, 842574, 2522415, 7552239, 22613578, 67714627, 202772197, 607215863, 1818375168, 5445371326, 16306993036, 48833947510, 146241553581, 437945846008, 1311506541151
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OFFSET
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1,2
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COMMENTS
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LINKS
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FORMULA
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Empirical: a(n) = 3*a(n-1) +a(n-2) +2*a(n-3) -11*a(n-4) -12*a(n-5) -9*a(n-6) +15*a(n-7) +23*a(n-8) +20*a(n-9) -6*a(n-10) -15*a(n-11) -12*a(n-12) -2*a(n-13) +3*a(n-14) +a(n-15)
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EXAMPLE
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Some solutions for n=4
..0..0..0....0..1..0....0..0..0....0..0..0....0..0..1....0..0..0....0..0..1
..0..0..0....1..0..1....0..1..0....0..0..0....0..0..0....0..0..0....0..0..0
..0..0..0....0..1..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0
..0..0..0....1..0..1....0..0..1....1..0..0....0..0..1....0..0..1....1..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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