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A263218
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Number of (n+1)X(2+1) 0..2 arrays with each row and column divisible by 5, read as a base-3 number with top and left being the most significant digits.
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1
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2, 14, 72, 343, 1920, 11444, 68112, 405019, 2422502, 14527358, 87130296, 522558079, 3134839248, 18808467356, 112848487824, 677075548723, 4062417593558, 24374464952438, 146246626666296, 877478675492551, 5264869525163232
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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) -16*a(n-2) +32*a(n-3) +35*a(n-4) -664*a(n-5) +1328*a(n-6) -2656*a(n-7) +3121*a(n-8) +6904*a(n-9) -13808*a(n-10) +27616*a(n-11) -40643*a(n-12) -6248*a(n-13) +12496*a(n-14) -24992*a(n-15) +37488*a(n-16)
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EXAMPLE
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Some solutions for n=4
..2..2..1....1..2..0....0..1..2....0..1..2....0..1..2....0..0..0....2..2..1
..1..0..1....2..2..1....1..2..0....1..2..0....1..0..1....1..2..0....1..0..1
..2..2..1....0..0..0....2..2..1....2..0..2....0..1..2....0..0..0....2..2..1
..1..0..1....0..1..2....1..0..1....0..0..0....1..0..1....2..2..1....2..0..2
..0..0..0....0..1..2....2..2..1....0..0..0....0..0..0....2..0..2....2..0..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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