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A239033
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Number of 6 X n 0..2 arrays with no element equal to the sum of elements to its left or one plus the sum of the elements above it, modulo 3.
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1
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8, 43, 212, 806, 2592, 7265, 18362, 42809, 93464, 193157, 380900, 721154, 1317296, 2330727, 4007402, 6713945, 10985936, 17591423, 27613220, 42554102, 64469600, 96133733, 141243690, 204670193, 292761032, 413706065, 577972820, 798822722
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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) = (1/8640)*n^9 - (61/20160)*n^8 + (263/3360)*n^7 - (1439/1440)*n^6 + (29843/2880)*n^5 - (194227/2880)*n^4 + (668597/2160)*n^3 - (1477657/1680)*n^2 + (59263/42)*n - 943 for n>2.
G.f.: x*(8 - 37*x + 142*x^2 - 339*x^3 + 592*x^4 - 811*x^5 + 996*x^6 - 1020*x^7 + 792*x^8 - 377*x^9 + 88*x^10 + 8*x^11) / (1 - x)^10.
a(n) = 10*a(n-1) - 45*a(n-2) + 120*a(n-3) - 210*a(n-4) + 252*a(n-5) - 210*a(n-6) + 120*a(n-7) - 45*a(n-8) + 10*a(n-9) - a(n-10) for n>12.
(End)
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EXAMPLE
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Some solutions for n=5:
..2..0..0..0..0....2..0..0..0..0....2..0..0..0..0....2..0..0..0..0
..2..0..0..0..0....1..0..0..2..2....2..0..0..0..0....2..0..0..0..0
..1..2..2..0..0....2..0..0..1..2....1..0..0..0..0....1..0..0..0..2
..2..1..1..2..2....2..0..0..0..0....2..0..0..0..0....1..2..2..0..1
..1..2..2..1..2....1..0..2..2..0....1..0..0..2..2....2..1..1..2..2
..1..2..1..0..0....1..2..1..2..1....1..0..0..2..1....1..0..2..1..2
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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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