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A296552
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Number of n X 6 0..1 arrays with each 1 horizontally, vertically or antidiagonally adjacent to 3 or 6 neighboring 1s.
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1
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1, 1, 5, 10, 18, 32, 62, 118, 227, 439, 839, 1592, 3037, 5823, 11144, 21287, 40672, 77755, 148635, 284114, 543117, 1038203, 1984469, 3793276, 7251035, 13860645, 26494780, 50645098, 96809194, 185052813, 353731968, 676165670, 1292504296
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OFFSET
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1,3
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LINKS
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FORMULA
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Empirical: a(n) = a(n-1) + 4*a(n-4) + a(n-5) + 3*a(n-6) + 6*a(n-7) + 2*a(n-9) + 4*a(n-10) + a(n-13).
Empirical g.f.: x*(1 + 4*x^2 + 5*x^3 + 4*x^4 + 9*x^5 + 6*x^6 + 2*x^7 + 6*x^8 + 4*x^9 + x^11 + x^12) / (1 - x - 4*x^4 - x^5 - 3*x^6 - 6*x^7 - 2*x^9 - 4*x^10 - x^13). - Colin Barker, Feb 23 2019
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EXAMPLE
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Some solutions for n=7:
..0..0..1..1..0..0. .0..0..0..0..0..0. .0..1..1..0..0..0. .0..0..1..1..0..0
..0..1..1..1..0..0. .0..0..1..1..0..0. .1..1..1..0..0..0. .0..1..1..1..0..0
..0..1..1..0..0..0. .0..1..1..1..0..0. .1..1..0..0..0..0. .0..1..1..0..1..1
..0..0..0..0..0..0. .0..1..1..0..0..0. .0..0..0..1..1..0. .0..0..0..1..1..1
..0..0..0..0..0..0. .0..0..0..1..1..0. .0..0..1..1..1..0. .0..0..0..1..1..0
..0..0..0..0..0..0. .0..0..1..1..1..0. .0..0..1..1..0..0. .0..0..0..0..0..0
..0..0..0..0..0..0. .0..0..1..1..0..0. .0..0..0..0..0..0. .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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