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A252547
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Number of (3+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 1 3 4 6 or 7 and every 3X3 column and antidiagonal sum not equal to 1 3 4 6 or 7
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1
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2142, 15480, 88146, 331884, 2576592, 15204660, 65274264, 519308064, 3103786152, 14646511152, 117255965760, 703300899408, 3514356996192, 28154584379520, 168981193312416, 871431684513984, 6978394143113472, 41882596925317440
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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) = 454*a(n-3) -60040*a(n-6) +2444800*a(n-9) -13041664*a(n-12) +16777216*a(n-15)
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EXAMPLE
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Some solutions for n=3
..0..1..3..0..1....0..0..1..0..0....2..2..3..2..2....1..0..0..1..3
..3..0..1..3..0....3..2..2..0..2....0..2..2..0..2....3..1..0..3..1
..2..1..1..2..1....2..3..2..2..3....0..1..0..3..1....1..1..2..1..1
..0..1..3..0..1....0..0..1..3..0....2..2..0..2..2....1..3..0..1..0
..3..0..1..3..3....0..2..2..3..2....0..2..2..3..2....0..1..3..3..1
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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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