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A239407
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Number of 3Xn 0..3 arrays with no element equal to one plus the sum of elements to its left or two plus the sum of the elements above it, modulo 4
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1
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12, 129, 1337, 13977, 144762, 1504399, 15591122, 161801518, 1677624003, 17403195529, 180479056305, 1871997954119, 19414915574725, 201369918597195, 2088509247416759, 21661501410101827, 224664541142404827
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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) = 8*a(n-1) +73*a(n-2) -446*a(n-3) -1413*a(n-4) +8070*a(n-5) +12185*a(n-6) -63420*a(n-7) -49358*a(n-8) +220534*a(n-9) +39486*a(n-10) -241802*a(n-11) +244780*a(n-12) -89648*a(n-13) -386680*a(n-14) -228008*a(n-15) +129984*a(n-16) -457816*a(n-17) -1064416*a(n-18) -330768*a(n-19) +556128*a(n-20) -351872*a(n-21) +769280*a(n-22) +407552*a(n-23) -200704*a(n-24) +32768*a(n-25)
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EXAMPLE
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Some solutions for n=4
..3..3..1..3....3..1..0..0....3..3..1..3....0..3..3..0....0..0..3..3
..0..2..1..3....2..2..3..1....2..2..2..2....0..0..0..3....0..0..0..2
..2..0..1..1....0..2..0..1....2..2..3..1....0..2..0..0....3..3..2..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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