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A222140
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Number of n X 4 0..4 arrays with no entry increasing mod 5 by 4 rightwards or downwards, starting with upper left zero.
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2
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64, 8788, 1206964, 165770032, 22767656980, 3127020364012, 429480137694664, 58986884432558548, 8101544704688334244, 1112705429924911477552, 152824358676750267429220, 20989638386627725143014812
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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) = 153*a(n-1) - 2197*a(n-2) + 6434*a(n-3).
Empirical g.f.: 4*x*(16 - 251*x + 752*x^2) / (1 - 153*x + 2197*x^2 - 6434*x^3). - Colin Barker, Mar 14 2018
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EXAMPLE
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Some solutions for n=3:
..0..0..1..2....0..0..1..2....0..1..1..2....0..0..1..4....0..1..1..2
..0..3..4..2....0..3..4..2....1..4..1..3....1..1..4..0....0..3..4..0
..0..1..1..2....2..3..0..3....3..0..1..1....1..2..4..1....2..0..2..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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