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A231840
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Number of 2Xn 0..3 arrays with no element less than a strict majority of its horizontal and antidiagonal neighbors
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1
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16, 50, 188, 760, 3309, 14666, 64607, 283479, 1243280, 5452114, 23905237, 104828007, 459770373, 2016638186, 8845269109, 38796696140, 170170211095, 746407664707, 3273942709889, 14360456936977, 62989372397071
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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) = 16*a(n-1) -120*a(n-2) +594*a(n-3) -2230*a(n-4) +6728*a(n-5) -16873*a(n-6) +35897*a(n-7) -65873*a(n-8) +105776*a(n-9) -149668*a(n-10) +188619*a(n-11) -211559*a(n-12) +213408*a(n-13) -191583*a(n-14) +154654*a(n-15) -110323*a(n-16) +68713*a(n-17) -37978*a(n-18) +15027*a(n-19) -6519*a(n-20) -1220*a(n-21) -499*a(n-22) -1885*a(n-23) -410*a(n-24) -615*a(n-25) -257*a(n-26) -118*a(n-27) -60*a(n-28) -15*a(n-29) -5*a(n-30) -a(n-31) for n>32
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EXAMPLE
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Some solutions for n=5
..1..1..1..0..0....3..3..3..3..2....2..1..1..2..1....3..0..0..0..0
..2..1..0..0..1....2..2..2..2..3....1..1..1..1..2....0..1..1..1..2
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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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