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A234124
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Number of (n+1) X (1+1) 0..6 arrays with every 2 X 2 subblock having the absolute values of all six edge and diagonal differences no larger than 1.
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1
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91, 469, 2413, 12457, 64441, 333883, 1731979, 8992639, 46723771, 242899381, 1263281581, 6572316673, 34201861129, 178020202699, 926739961723, 4825035300439, 25123800838123, 130828761714565, 681313452720301
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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) = 10*a(n-1) - 24*a(n-2) - 18*a(n-3) + 57*a(n-4) + 54*a(n-5) + 12*a(n-6).
Empirical g.f.: x*(91 - 441*x - 93*x^2 + 1221*x^3 + 1038*x^4 + 228*x^5) / (1 - 10*x + 24*x^2 + 18*x^3 - 57*x^4 - 54*x^5 - 12*x^6). - Colin Barker, Oct 12 2018
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EXAMPLE
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Some solutions for n=5:
..3..3....4..5....1..0....1..0....2..2....5..5....6..5....1..1....2..3....3..2
..3..2....4..5....1..0....1..1....2..3....5..4....5..5....1..1....3..2....2..3
..3..3....4..4....0..0....2..2....3..3....5..4....4..4....2..2....3..2....2..2
..2..2....5..5....0..1....2..3....4..4....4..5....4..3....1..2....3..2....1..2
..2..3....5..4....0..1....3..3....3..3....4..4....4..4....2..2....3..2....2..2
..2..3....4..5....1..1....3..4....4..4....4..3....4..3....3..2....3..2....1..1
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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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