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A234107
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Number of (n+1) X (1+1) 0..4 arrays with every 2 X 2 subblock having the sum of the absolute values of all six edge and diagonal differences equal to 12.
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1
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56, 186, 604, 2064, 6964, 24156, 83012, 290164, 1007972, 3540836, 12393060, 43708804, 153873060, 544613636, 1926294628, 6839634244, 24285641508, 86475603716, 308037991396, 1099585403844, 3927295071396, 14049115042436
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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) = 5*a(n-1) + 6*a(n-2) - 50*a(n-3) + 16*a(n-4) + 80*a(n-5) - 16*a(n-6).
Empirical g.f.: 2*x*(28 - 47*x - 331*x^2 + 364*x^3 + 712*x^4 - 152*x^5) / ((1 - 2*x)*(1 - 2*x - 4*x^2)*(1 - x - 10*x^2 + 2*x^3)). - Colin Barker, Oct 12 2018
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EXAMPLE
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Some solutions for n=5:
..0..1....4..2....4..1....0..4....4..0....0..2....4..0....3..0....0..4....3..4
..1..4....2..0....4..1....4..4....2..2....4..2....4..4....3..0....1..1....3..0
..0..1....4..2....4..1....0..4....4..0....0..2....1..1....3..0....4..4....3..0
..4..1....2..0....1..4....4..4....1..1....4..2....4..0....0..3....1..1....0..3
..4..1....4..2....1..0....0..4....4..4....2..0....1..1....4..3....4..4....3..4
..0..1....2..0....4..1....2..2....4..0....4..2....4..4....0..3....0..4....0..3
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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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