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A208635
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Number of n X 6 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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32, 95, 309, 1042, 3577, 12404, 43284, 151656, 532795, 1875161, 6607478, 23301225, 82215220, 290187784, 1024490960, 3617470935, 12774594765, 45114821146, 159335044937, 562751474084, 1987608261228, 7020221345560, 24795605196403
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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) = 7*a(n-1) - 15*a(n-2) + 10*a(n-3) - a(n-4).
Empirical g.f.: x*(32 - 129*x + 124*x^2 - 16*x^3) / ((1 - x)*(1 - 6*x + 9*x^2 - x^3)). - Colin Barker, Jul 05 2018
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EXAMPLE
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Some solutions for n=4:
..0..1..1..0..1..0....0..0..1..0..0..0....0..0..1..0..0..1....0..0..0..1..0..0
..1..0..1..0..1..1....1..0..1..1..1..0....1..0..1..1..0..0....1..1..0..1..1..0
..0..1..0..1..0..0....1..0..0..0..1..0....1..0..0..1..1..0....0..1..0..0..1..1
..0..1..0..1..1..1....0..1..1..0..1..1....1..1..0..0..1..0....1..0..1..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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