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A207456
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Number of 5 X n 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 1 0 1 vertically.
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1
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10, 100, 270, 1450, 5200, 23530, 92610, 396100, 1610950, 6754210, 27799200, 115710130, 478341370, 1985702500, 8222193630, 34098329530, 141276194800, 585672013210, 2427100765650, 10060368444100, 41694947333590
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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) = a(n-1) + 13*a(n-2) + 4*a(n-3) - 16*a(n-4).
Empirical g.f.: 10*x*(1 + 9*x + 4*x^2 - 16*x^3) / (1 - x - 13*x^2 - 4*x^3 + 16*x^4). - Colin Barker, Jun 23 2018
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EXAMPLE
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Some solutions for n=5:
1 1 1 1 1 1 0 1 1 0 0 1 0 1 0 0 1 0 1 0
1 1 1 1 1 1 1 0 1 1 1 1 0 1 0 1 1 0 1 0
0 1 0 1 1 0 1 0 1 0 1 1 0 1 0 0 1 0 1 0
0 1 0 1 0 0 1 0 1 0 1 1 0 1 0 0 1 0 1 0
0 1 0 1 0 0 1 0 1 0 1 1 0 1 0 0 1 0 1 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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