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A252204
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Number of (n+2)X(2+2) 0..3 arrays with every 3X3 subblock row and column sum equal to 1 3 4 6 or 7 and every 3X3 diagonal and antidiagonal sum not equal to 1 3 4 6 or 7
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1
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4743, 5178, 17276, 44322, 215814, 932474, 2568954, 12883538, 56985498, 157484310, 797509638, 3566734178, 9868152522, 50206875026, 225779395146, 624968086326, 3187016754054, 14371363263554, 39789382386954, 203137189251218
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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) = 118*a(n-3) -4263*a(n-6) +55050*a(n-9) -221016*a(n-12) +206976*a(n-15) +225280*a(n-18) -262144*a(n-21) for n>25
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EXAMPLE
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Some solutions for n=4
..1..3..0..1....0..3..1..3....3..0..1..0....1..2..1..1....3..0..1..0
..0..2..2..0....0..0..1..0....1..1..2..1....3..1..3..3....1..1..2..1
..0..2..2..0....1..1..2..1....0..0..1..0....0..1..0..3....3..3..1..0
..1..3..0..1....3..3..1..0....0..0..1..0....1..2..1..1....3..3..1..0
..3..2..2..3....0..0..1..3....1..1..2..1....0..1..0..3....1..1..2..1
..3..2..2..3....1..1..2..1....0..3..1..0....0..1..3..0....0..3..1..0
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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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