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A207121
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Number of nX6 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 0 1 and 0 1 1 vertically
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1
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21, 441, 2499, 14161, 49861, 175561, 475984, 1290496, 2958144, 6780816, 13816824, 28153636, 52561236, 98128836, 171205398, 298702089, 493723461, 816073489, 1290571359, 2040961329, 3110933397, 4741837321, 7005780418, 10350620644
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OFFSET
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1,1
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COMMENTS
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Column 6 of A207123
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LINKS
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R. H. Hardin, Table of n, a(n) for n = 1..210
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FORMULA
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Empirical: a(n) = 2*a(n-1) +10*a(n-2) -22*a(n-3) -44*a(n-4) +110*a(n-5) +110*a(n-6) -330*a(n-7) -165*a(n-8) +660*a(n-9) +132*a(n-10) -924*a(n-11) +924*a(n-13) -132*a(n-14) -660*a(n-15) +165*a(n-16) +330*a(n-17) -110*a(n-18) -110*a(n-19) +44*a(n-20) +22*a(n-21) -10*a(n-22) -2*a(n-23) +a(n-24)
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EXAMPLE
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Some solutions for n=4
..0..1..1..1..0..1....0..0..0..0..0..0....1..0..1..1..1..0....1..0..1..1..1..0
..0..0..0..0..0..0....1..0..0..0..0..0....0..1..1..1..1..0....0..1..1..0..1..1
..0..0..0..0..0..0....0..0..0..0..0..0....0..0..0..0..0..0....0..0..0..0..0..0
..0..0..0..0..0..0....0..0..0..0..0..0....0..0..0..0..0..0....0..0..0..0..0..0
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CROSSREFS
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Sequence in context: A207246 A208167 A207066 * A207440 A188691 A207430
Adjacent sequences: A207118 A207119 A207120 * A207122 A207123 A207124
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KEYWORD
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nonn
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AUTHOR
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R. H. Hardin Feb 15 2012
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STATUS
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approved
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