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A189606
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Number of nX5 array permutations with each element not moving, or moving one space E, S or NW
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1
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1, 28, 256, 2853, 30283, 321815, 3414588, 36212912, 383990913, 4071436782, 43168209556, 457694879893, 4852734814404, 51451313282657, 545514314383676, 5783833141059232, 61323273361025444, 650181923557415105
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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) = 13*a(n-1) -13*a(n-2) -128*a(n-3) -146*a(n-4) +1071*a(n-5) +769*a(n-6) -749*a(n-7) -2673*a(n-8) +3566*a(n-9) -13757*a(n-10) +7250*a(n-11) -4937*a(n-12) -1246*a(n-13) +3164*a(n-14) +189*a(n-15) -984*a(n-16) +566*a(n-17) +329*a(n-18) -189*a(n-19) +54*a(n-20) +27*a(n-21) for n>22
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EXAMPLE
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Some solutions for 3X5
..6..0..2..3..4....0..7..8..2..3....0..7..2..3..4....0..1..2..3..4
.11..1..7.14..9....5..1.13.14..4....5..1.13.14..8...11..5..7..8..9
..5.10.12..8.13...10..6.11.12..9...10..6.11.12..9...10..6.12.13.14
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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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