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A218892
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Number of n X 3 arrays of the minimum value of corresponding elements and their horizontal, diagonal or antidiagonal neighbors in a random 0..1 n X 3 array.
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1
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4, 18, 72, 286, 1162, 4700, 19046, 77198, 312944, 1268694, 5143506, 20852924, 84542894, 342758566, 1389632608, 5633935678, 22841460250, 92605309212, 375446383830, 1522158836638, 6171234143440, 25019814013190, 101436937848962
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OFFSET
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1,1
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COMMENTS
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Column 3 of A218897.
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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) = 4*a(n-1) + 2*a(n-2) - 5*a(n-3) - 8*a(n-4) - 4*a(n-5).
Empirical g.f.: 2*x*(2 + x - 4*x^2 - 9*x^3 - 2*x^4) / (1 - 4*x - 2*x^2 + 5*x^3 + 8*x^4 + 4*x^5). - Colin Barker, Jul 24 2018
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EXAMPLE
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Some solutions for n=3:
..0..0..1....1..0..1....0..0..0....0..0..0....0..0..1....0..0..0....0..0..1
..1..0..1....0..0..0....0..0..0....1..0..0....0..0..1....0..0..0....1..0..0
..0..0..0....1..0..0....0..0..0....1..0..1....1..0..1....1..0..1....1..0..0
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CROSSREFS
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Cf. A218897.
Sequence in context: A159715 A027261 A290919 * A307566 A117615 A267450
Adjacent sequences: A218889 A218890 A218891 * A218893 A218894 A218895
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KEYWORD
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nonn
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AUTHOR
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R. H. Hardin, Nov 08 2012
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STATUS
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approved
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