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A252377
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Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 3 5 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 3 5 6 or 7
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1
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578, 540, 588, 651, 785, 904, 1051, 1290, 1543, 1902, 2392, 2959, 3827, 4965, 6347, 8484, 11355, 14882, 20270, 27738, 36892, 50720, 70283, 94180, 130033, 181321, 243827, 337271, 471676, 635273, 879421, 1231489, 1659757, 2298382, 3220359
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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) = 5*a(n-3) -8*a(n-6) +5*a(n-9) -a(n-12) for n>22
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EXAMPLE
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Some solutions for n=4
..3..0..0....3..1..2....1..3..2....0..1..2....3..0..3....0..2..1....0..3..0
..3..1..3....3..0..0....3..0..0....2..0..3....2..3..0....0..0..0....1..3..2
..3..3..1....2..1..0....0..1..2....2..1..3....3..1..1....1..2..0....1..2..0
..3..0..0....3..1..1....1..0..2....0..1..2....3..0..0....0..2..1....0..3..0
..3..1..3....3..0..0....0..0..0....0..0..3....3..1..3....0..0..0....1..3..1
..3..3..1....3..1..3....0..1..2....2..1..3....3..3..1....1..2..0....1..2..3
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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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