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A202790
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Number of n X 3 binary arrays with every one adjacent to another one horizontally, diagonally, antidiagonally or vertically.
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1
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4, 50, 398, 3018, 23436, 182430, 1417772, 11017196, 85621362, 665418194, 5171353118, 40189602848, 312336995590, 2427354106352, 18864392868124, 146606264807250, 1139363300400646, 8854660691296250, 68814763405175276
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OFFSET
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1,1
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COMMENTS
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Column 3 of A202795.
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LINKS
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R. H. Hardin, Table of n, a(n) for n = 1..210
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FORMULA
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Empirical: a(n) = 7*a(n-1) +2*a(n-2) +29*a(n-3) +16*a(n-4).
Empirical g.f.: 2*x*(2 + 11*x + 20*x^2 + 8*x^3) / (1 - 7*x - 2*x^2 - 29*x^3 - 16*x^4). - Colin Barker, Jun 01 2018
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EXAMPLE
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Some solutions for n=5:
..1..0..1....1..0..0....1..0..0....1..1..0....1..1..0....1..1..1....0..1..0
..1..1..0....0..1..0....1..1..0....1..0..1....1..0..1....1..0..0....0..1..1
..0..1..0....1..1..0....1..1..1....1..1..0....1..1..0....1..1..1....1..1..0
..1..1..0....0..1..0....0..1..0....1..1..0....1..1..1....1..1..0....1..1..0
..0..0..1....0..1..0....1..0..0....0..1..0....1..0..0....0..1..0....0..1..1
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CROSSREFS
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Cf. A202795.
Sequence in context: A240396 A197473 A219566 * A231833 A028455 A232731
Adjacent sequences: A202787 A202788 A202789 * A202791 A202792 A202793
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KEYWORD
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nonn
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AUTHOR
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R. H. Hardin, Dec 24 2011
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STATUS
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approved
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