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A233910
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Number of (n+1)X(1+1) 0..7 arrays with every 2X2 subblock having the sum of the squares of the edge differences equal to 30, and no two adjacent values equal
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1
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160, 640, 2440, 9612, 36976, 145004, 559736, 2189924, 8470344, 33088100, 128155456, 500055876, 1938715672, 7558416852, 29325538832, 114258452900, 443550616168, 1727342374724, 6708320872096, 26115152683348, 101452849075768
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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-2) +6*a(n-3) -177*a(n-4) -52*a(n-5) +516*a(n-6) +80*a(n-7) -646*a(n-8) +42*a(n-9) +284*a(n-10) -80*a(n-11)
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EXAMPLE
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Some solutions for n=5
..2..0....3..2....1..0....2..6....3..2....2..5....5..6....4..6....6..7....0..2
..1..4....0..4....5..2....4..7....1..5....0..4....7..3....5..2....2..5....1..5
..2..6....2..5....4..6....2..6....3..6....2..5....4..5....7..3....3..7....4..6
..4..7....3..7....5..2....4..7....7..5....3..1....6..2....5..2....2..4....1..2
..2..3....2..4....7..3....2..3....3..6....6..2....4..1....4..6....3..0....4..0
..5..7....6..7....4..5....5..1....4..2....4..1....6..2....1..2....5..1....2..3
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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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