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A233152
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Number of n X 5 0..2 arrays with no element x(i,j) adjacent to value 2-x(i,j) horizontally or antidiagonally.
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1
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48, 648, 8856, 121176, 1658232, 22692312, 310536504, 4249585944, 58154132088, 795819434328, 10890517137336, 149033007242136, 2039465800159992, 27909392872041432, 381930508677741624, 5226588558469378584
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OFFSET
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1,1
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LINKS
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FORMULA
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Empirical: a(n) = 15*a(n-1) - 18*a(n-2).
Empirical g.f.: 24*x*(2 - 3*x) / (1 - 15*x + 18*x^2). - Colin Barker, Oct 08 2018
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EXAMPLE
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Some solutions for n=4:
..1..2..1..2..2....0..1..2..1..0....2..1..0..0..0....1..2..1..2..2
..2..2..1..2..2....0..1..0..1..2....2..1..0..1..2....2..2..2..2..2
..2..2..1..2..1....0..1..2..1..0....2..1..0..1..2....2..1..2..1..2
..1..2..1..2..2....2..1..0..1..2....0..0..0..1..2....0..1..0..1..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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