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A221224
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Number of n X 3 arrays of occupancy after each element stays put or moves to some king-move neighbor.
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1
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8, 400, 18768, 867776, 39983152, 1840507104, 84698310960, 3897368193376, 179330419695472, 8251471025928064, 379670549581978384, 17469551012762540960, 803815384904102897232, 36985439805161039680544
(list;
graph;
refs;
listen;
history;
text;
internal format)
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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) = 77*a(n-1) - 1710*a(n-2) + 13925*a(n-3) - 39617*a(n-4) + 25616*a(n-5) - 5184*a(n-6).
Empirical g.f.: 8*x*(1 - 27*x + 206*x^2 - 595*x^3 + 577*x^4 - 146*x^5) / (1 - 77*x + 1710*x^2 - 13925*x^3 + 39617*x^4 - 25616*x^5 + 5184*x^6). - Colin Barker, Aug 04 2018
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EXAMPLE
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Some solutions for n=3:
..0..2..0....1..1..0....1..0..0....0..1..0....2..1..3....1..0..1....0..1..4
..0..4..0....1..4..0....1..5..1....1..1..3....0..0..1....0..1..1....1..1..0
..0..1..2....1..0..1....0..1..0....0..2..1....0..1..1....1..2..2....0..0..2
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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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