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A252681
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Number of (2+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 2 5 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 2 5 6 or 7
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1
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750, 630, 1005, 1525, 3185, 6645, 10933, 24685, 54782, 91577, 211344, 479362, 805863, 1878870, 4316287, 7281075, 17071625, 39565761, 66917777, 157482493, 367387630, 622655713, 1469264172, 3444892538, 5848122279, 13827395422
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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) = 24*a(n-3) -203*a(n-6) +722*a(n-9) -959*a(n-12) -64*a(n-15) +1043*a(n-18) -682*a(n-21) +120*a(n-24) for n>33
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EXAMPLE
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Some solutions for n=4
..2..0..3..2..2..3....0..2..0..3..2..0....0..1..1..0..1..1....1..3..1..1..0..1
..1..0..1..1..0..1....1..1..0..1..1..0....0..2..3..0..2..0....0..0..2..0..3..2
..1..1..0..1..1..0....3..1..1..0..1..1....1..1..0..1..1..0....3..1..1..0..1..1
..2..0..0..2..3..0....0..2..3..0..2..0....0..1..1..0..1..1....1..0..1..1..0..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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