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A237854
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Number of (n+1)X(3+1) 0..1 arrays with no element greater than all horizontal neighbors or less than all vertical neighbors
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1
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7, 41, 184, 773, 3373, 15038, 66838, 295601, 1306735, 5781785, 25589556, 113242992, 501098184, 2217363176, 9812031225, 43419245331, 192134011624, 850208955685, 3762246587434, 16648265214303, 73670007635534, 325996107221214
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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) = 5*a(n-1) -6*a(n-2) +13*a(n-3) +11*a(n-4) -5*a(n-5) +4*a(n-6) +9*a(n-7) -10*a(n-8) -10*a(n-9) +a(n-11)
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EXAMPLE
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Some solutions for n=5
..1..1..1..1....0..0..1..1....0..1..1..1....1..1..1..0....1..1..0..0
..1..1..1..1....0..0..1..1....0..0..0..0....1..1..0..0....1..1..0..0
..1..1..1..0....1..1..1..0....0..0..0..0....1..1..0..0....0..1..1..1
..0..0..0..0....1..1..1..0....0..0..0..0....1..1..0..0....0..0..1..1
..0..0..0..0....0..1..1..1....0..1..1..0....0..0..0..0....0..0..1..1
..1..1..1..0....0..1..1..1....0..1..1..1....0..0..1..1....0..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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