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A237317
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Number of (n+1) X (1+1) 0..2 arrays with the maximum plus the upper median plus the minimum minus the lower median of every 2 X 2 subblock differing from its horizontal and vertical neighbors by exactly one.
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1
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81, 348, 1508, 6608, 28772, 123888, 536848, 2352448, 10242832, 44104128, 191117888, 837471488, 3646448192, 15701069568, 68037968128, 298139849728, 1298135556352, 5589580766208, 24221516653568, 106137786503168
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OFFSET
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1,1
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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) = 356*a(n-4) for n>5.
Empirical g.f.: x*(81 + 348*x + 1508*x^2 + 6608*x^3 - 64*x^4) / (1 - 356*x^4). - Colin Barker, Oct 22 2018
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EXAMPLE
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Some solutions for n=5:
..1..0....1..1....2..2....1..1....0..0....2..1....0..0....2..2....1..1....1..0
..1..2....0..0....0..2....0..2....1..2....2..2....1..2....1..0....0..1....2..0
..0..0....1..2....0..1....1..2....0..1....2..0....1..0....1..2....2..1....2..2
..2..2....0..1....1..2....1..0....0..2....0..1....0..0....1..1....1..1....2..1
..1..0....2..2....1..1....0..2....1..1....1..2....0..2....2..2....0..2....1..0
..1..0....2..0....1..1....2..2....2..1....0..0....1..2....2..1....2..1....2..2
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CROSSREFS
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Column 1 of A237324.
Sequence in context: A236730 A237324 A237730 * A237723 A237472 A237465
Adjacent sequences: A237314 A237315 A237316 * A237318 A237319 A237320
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KEYWORD
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nonn
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AUTHOR
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R. H. Hardin, Feb 06 2014
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STATUS
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approved
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