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A251508
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Number of (n+1)X(1+1) 0..4 arrays with every 2X2 subblock summing to a prime
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1
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234, 2264, 21862, 211680, 2047194, 19818328, 191708742, 1855695600, 17952272890, 173762374600, 1681099972966, 16270774744064, 157421932250266, 1523571767403576, 14741276442715142, 142665595478323984
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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) = 2*a(n-1) +115*a(n-2) -138*a(n-3) -2996*a(n-4) +2512*a(n-5) +26576*a(n-6) -15680*a(n-7) -65856*a(n-8) +34560*a(n-9)
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EXAMPLE
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Some solutions for n=3
..3..0....4..3....2..1....1..2....1..0....4..2....0..0....1..0....1..1....2..2
..0..0....4..2....2..0....0..2....0..1....1..0....3..4....4..0....2..1....4..3
..0..2....4..3....0..0....0..1....4..2....1..0....4..0....1..0....0..2....1..3
..1..0....1..3....1..2....4..2....2..3....0..4....0..3....1..1....3..2....3..4
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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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