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A202331
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Number of (n+1) X 5 binary arrays with consecutive windows of two bits considered as a binary number nondecreasing in every row and column.
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1
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49, 129, 289, 576, 1052, 1796, 2906, 4501, 6723, 9739, 13743, 18958, 25638, 34070, 44576, 57515, 73285, 92325, 115117, 142188, 174112, 211512, 255062, 305489, 363575, 430159, 506139, 592474, 690186, 800362, 924156, 1062791, 1217561
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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) = (1/60)*n^5 + (3/8)*n^4 + 3*n^3 + (89/8)*n^2 + (1169/60)*n + 15.
G.f.: x*(49 - 165*x + 250*x^2 - 203*x^3 + 86*x^4 - 15*x^5) / (1 - x)^6.
a(n) = 6*a(n-1) - 15*a(n-2) + 20*a(n-3) - 15*a(n-4) + 6*a(n-5) - a(n-6) for n>6.
(End)
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EXAMPLE
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Some solutions for n=5:
..0..0..0..0..0....0..0..0..0..0....0..0..0..1..0....0..0..0..0..0
..0..0..0..1..0....0..0..0..0..0....0..0..0..1..0....0..0..0..0..0
..0..0..0..1..0....0..0..0..0..0....0..0..0..1..1....0..0..0..1..0
..0..0..0..1..0....0..0..0..1..1....0..0..0..1..1....0..0..1..1..1
..0..1..1..1..1....0..0..0..1..1....1..1..1..1..1....1..1..1..1..1
..0..0..0..1..1....0..0..1..1..1....0..0..1..1..1....1..1..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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