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A189644
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Number of nX3 array permutations with each element moving zero or one space horizontally, diagonally or antidiagonally
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1
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3, 33, 263, 2161, 17655, 144353, 1180167, 9648721, 78885143, 644942273, 5272862503, 43109407281, 352450114615, 2881530764193, 23558566731847, 192608065601041, 1574708145738583, 12874360876413313, 105257071556189543
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OFFSET
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1,1
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COMMENTS
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Column 3 of A189650
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LINKS
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R. H. Hardin, Table of n, a(n) for n = 1..200
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FORMULA
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Empirical: a(n)=9*a(n-1)-6*a(n-2)-8*a(n-3)+16*a(n-4)
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EXAMPLE
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Some solutions for 4X3
..0..1..2....1..0..2....1..0..4....4..0..2....0..2..1....0..3..4....1..0..2
..7..5..4....3..8..5....3..2..5....3..5..1....3..4..5....1..2..7....3..6..5
..6..3.10....6..9..4...10..6..7...10..6..8....7..9..8....6..5.10....7..8..4
..9..8.11....7.11.10....9..8.11....9.11..7...10..6.11....9..8.11....9.10.11
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CROSSREFS
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Sequence in context: A203560 A195578 A206950 * A003129 A190542 A180416
Adjacent sequences: A189641 A189642 A189643 * A189645 A189646 A189647
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KEYWORD
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nonn
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AUTHOR
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R. H. Hardin Apr 24 2011
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STATUS
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approved
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