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A252946
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Number of (n+2)X(2+2) 0..2 arrays with every consecutive three elements in every row, column and nw-se diagonal having exactly two distinct values, and new values 0 upwards introduced in row major order
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1
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747, 2988, 12915, 57978, 262494, 1192149, 5419521, 24648309, 112122162, 510068277, 2320483212, 10556851032, 48027819627, 218500501500, 994059717210, 4522438970532, 20574677747547, 93603784061979, 425847190478391
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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) = 6*a(n-1) -5*a(n-2) -8*a(n-3) +4*a(n-4) -7*a(n-5) +14*a(n-6) +19*a(n-7) -14*a(n-8) -12*a(n-9) -24*a(n-10) -47*a(n-11) +18*a(n-12) +31*a(n-13) +7*a(n-14) +40*a(n-15) -5*a(n-16) +a(n-17) -11*a(n-18) -12*a(n-19) +2*a(n-20) +5*a(n-21) -a(n-22)
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EXAMPLE
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Some solutions for n=4
..0..0..1..1....0..1..0..0....0..1..1..0....0..0..1..1....0..1..1..0
..0..1..1..0....2..2..0..0....1..1..0..0....0..2..0..2....1..2..1..1
..1..1..0..0....2..1..2..1....1..0..0..1....2..0..0..1....0..1..0..0
..1..2..1..1....1..2..2..0....0..0..1..0....2..2..1..2....0..1..0..0
..2..1..1..0....1..1..0..1....1..1..0..0....1..0..0..1....1..2..1..1
..1..2..2..1....0..2..2..0....1..0..0..1....2..0..0..2....0..1..0..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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