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A260203
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Number of (n+2)X(4+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000000 00000001 or 00010001
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1
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220, 479, 1857, 5998, 20408, 71846, 245486, 841296, 2905978, 9992478, 34348500, 118254574, 406871094, 1399624310, 4816056622, 16570641810, 57011471540, 196158495144, 674916008534, 2322129167778, 7989626498572, 27489503304114
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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) = a(n-1) +2*a(n-2) +18*a(n-3) +17*a(n-4) +7*a(n-5) -40*a(n-6) -78*a(n-7) -21*a(n-8) +88*a(n-9) +62*a(n-10) -49*a(n-11) -24*a(n-12) +9*a(n-13) -18*a(n-14) +2*a(n-15) +9*a(n-16) +4*a(n-17) +4*a(n-18) for n>19
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EXAMPLE
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Some solutions for n=4
..0..0..0..0..0..0....0..0..0..0..0..0....0..1..0..0..0..0....1..0..0..1..0..0
..0..1..0..0..0..0....0..0..0..1..0..0....0..0..0..0..0..0....0..0..0..0..0..0
..0..0..0..0..0..0....1..0..0..0..0..0....0..0..0..0..0..1....0..0..0..0..0..0
..0..0..0..0..0..0....0..0..0..0..0..0....0..0..1..0..0..0....0..0..0..0..0..0
..0..0..0..0..0..1....0..0..0..0..0..1....0..0..0..0..0..0....0..0..0..0..0..0
..0..0..0..0..0..0....0..1..0..0..0..0....0..0..0..0..0..0....0..1..0..0..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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