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A188841
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Number of n X 7 binary arrays without the pattern 0 1 diagonally or vertically.
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1
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128, 987, 3280, 7753, 15504, 28101, 47652, 76912, 119416, 179630, 263120, 376740, 528840, 729495, 990756, 1326924, 1754848, 2294248, 2968064, 3802832, 4829088, 6081801, 7600836, 9431448, 11624808, 14238562, 17337424, 20993804, 25288472
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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) = (1/5040)*n^7 + (1/72)*n^6 + (143/360)*n^5 + (53/9)*n^4 + (33667/720)*n^3 + (12679/72)*n^2 + (9439/70)*n - 572 for n>4.
Empirical g.f.: x*(128 - 37*x - 1032*x^2 + 1981*x^3 - 992*x^4 - 605*x^5 + 700*x^6 - 58*x^7 - 96*x^8 + 3*x^9 + 8*x^10 + x^11) / (1 - x)^8. - Colin Barker, May 01 2018
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EXAMPLE
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Some solutions for 3 X 7:
..1..1..0..0..1..1..1....1..1..1..1..1..1..1....1..0..0..1..1..0..0
..1..1..0..0..0..1..1....1..1..0..1..1..1..1....1..0..0..0..1..0..0
..1..1..0..0..0..0..0....0..0..0..0..0..0..0....1..0..0..0..0..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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