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A208640
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Number of 5 X n 0..1 arrays with new values 0..1 introduced in row major order and no element equal to more than one of its immediate leftward or upward or right-upward antidiagonal neighbors.
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1
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16, 89, 284, 722, 1652, 3577, 7504, 15448, 31440, 63543, 127884, 256718, 514556, 1030421, 2062360, 4126468, 8254936, 16512147, 33026868, 66056634, 132116516, 264236657, 528477344, 1056959152, 2113923232, 4227851887, 8455709724
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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) = 6*a(n-1) - 14*a(n-2) + 16*a(n-3) - 9*a(n-4) + 2*a(n-5) for n>7.
G.f.: x*(16 - 7*x - 26*x^2 + 8*x^3 + 16*x^4 - 2*x^5 - 4*x^6) / ((1 - x)^4*(1 - 2*x)).
a(n) = -84 + 63*2^n - (191*n)/6 - 4*n^2 - n^3/6 for n>2.
(End)
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EXAMPLE
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Some solutions for n=4:
..0..0..0..1....0..1..1..0....0..0..1..0....0..0..0..0....0..0..1..0
..1..1..0..1....0..0..1..0....1..0..1..0....1..1..1..0....1..0..1..0
..0..1..0..0....1..0..1..1....1..0..1..0....0..0..1..1....0..1..0..1
..0..1..1..1....1..0..0..1....1..0..1..0....1..0..0..1....1..0..1..0
..1..0..0..0....0..1..0..1....1..0..1..0....1..1..0..1....0..1..0..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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