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A189451
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Number of 3Xn array permutations with each element moving zero or one space horizontally or diagonally
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1
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1, 13, 80, 666, 5080, 40106, 313136, 2455013, 19221095, 150562121, 1179185280, 9235771513, 72336253737, 566554489205, 4437377818704, 34754532606346, 272205182385544, 2131971340412858, 16698071766102576, 130782997877002493
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OFFSET
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1,2
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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) +26*a(n-2) -72*a(n-3) -195*a(n-4) +284*a(n-5) +555*a(n-6) -424*a(n-7) -555*a(n-8) +284*a(n-9) +195*a(n-10) -72*a(n-11) -26*a(n-12) +6*a(n-13) +a(n-14)
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EXAMPLE
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Some solutions for 3X3
..1..0..2....0..2..1....0..1..2....0..2..1....0..1..2....1..0..2....0..5..2
..3..4..5....3..8..5....4..3..5....4..3..5....4..3..5....7..5..4....3..4..1
..7..6..8....6..7..4....6..8..7....6..8..7....7..6..8....6..3..8....6..8..7
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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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