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A203084
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Number of (n+2) X 3 binary arrays avoiding patterns 000 and 101 in rows and columns.
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2
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98, 253, 621, 1575, 4000, 10057, 25384, 64140, 161819, 408415, 1031041, 2602296, 6568305, 16579362, 41847510, 105626421, 266611217, 672949667, 1698582936, 4287374163, 10821707646, 27314936026, 68945297129, 174023973205
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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) + a(n-2) + 6*a(n-3) + 2*a(n-4) + 3*a(n-5) - a(n-6) - a(n-8) - a(n-9) - a(n-10).
Empirical g.f.: x*(98 + 155*x + 270*x^2 + 113*x^3 + 90*x^4 - 44*x^5 - 26*x^6 - 61*x^7 - 53*x^8 - 36*x^9) / (1 - x - x^2 - 6*x^3 - 2*x^4 - 3*x^5 + x^6 + x^8 + x^9 + x^10). - Colin Barker, Mar 03 2018
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EXAMPLE
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Some solutions for n=3:
1 0 0 1 1 0 1 1 0 0 1 0 0 0 1 1 1 1 1 0 0
1 1 0 1 1 0 1 1 1 1 0 0 1 1 1 1 1 0 1 1 0
1 1 1 1 1 1 1 1 1 0 0 1 1 0 0 1 1 0 0 1 1
1 1 1 0 1 1 1 1 1 0 1 1 1 0 0 0 1 1 0 1 1
0 1 0 0 0 1 0 1 0 1 1 0 0 1 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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