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A256023
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Number of (n+2)X(2+2) 0..1 arrays with no 3x3 subblock diagonal sum 0 or 1 and no antidiagonal sum 0 or 1 and no row sum 1 and no column sum 1
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1
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68, 164, 484, 1302, 3500, 9820, 27424, 76068, 212126, 592302, 1651552, 4606638, 12854658, 35865050, 100061478, 279186256, 778969128, 2173402654, 6064060764, 16919528420, 47207600896, 131715146500, 367502127158, 1025377787750
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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) = 3*a(n-1) -a(n-2) +5*a(n-3) -9*a(n-4) -5*a(n-5) -3*a(n-6) +7*a(n-7) +7*a(n-8) +4*a(n-9) -3*a(n-10) -2*a(n-11) -2*a(n-12)
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EXAMPLE
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Some solutions for n=4
..1..0..1..1....1..0..1..1....0..1..1..0....1..1..0..1....1..1..0..1
..1..1..1..1....1..1..1..1....1..1..1..1....0..1..1..1....1..1..1..0
..1..1..0..1....1..1..1..1....1..1..1..1....1..1..1..1....1..1..1..1
..1..1..1..1....0..1..1..0....1..1..0..1....1..1..1..1....0..1..1..1
..1..1..1..0....1..1..1..1....0..1..1..1....1..1..1..0....1..1..1..1
..0..1..1..1....1..1..1..1....1..1..1..0....1..1..0..1....1..1..1..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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