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A264361
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Number of (n+1) X (5+1) arrays of permutations of 0..n*6+5 with each element having directed index change 0,0 0,2 1,0 or -1,-2.
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1
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36, 400, 5184, 65536, 831744, 10549504, 133818624, 1697440000, 21531453696, 273119121664, 3464422799616, 43945019842816, 557427566889216, 7070778289926400, 89690407502010624, 1137692184365383936
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OFFSET
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1,1
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LINKS
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FORMULA
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Empirical: a(n) = 11*a(n-1) + 22*a(n-2) - 8*a(n-3).
Empirical g.f.: 4*x*(9 + x - 2*x^2) / ((1 + 2*x)*(1 - 13*x + 4*x^2)). - Colin Barker, Jan 07 2019
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EXAMPLE
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Some solutions for n=4:
..0..9.10.11..2..3....8..1..0..3..2..5....8..9..2..1..4..5....0..9.10..3..2..5
..6..1..8..7..4..5....6.15.16..9..4.11....0..7..6..3.10.11....6..1..8.17..4.11
.12.21.14.13.16.15...12..7.22.23.10.17...20.21.14.23.16.15...12..7.14.13.16.15
.26.27.28.29.20.17...26.13.14.29.20.21...12.13.18.19.22.17...26.27.28.19.20.23
.18.19.24.25.22.23...18.19.24.25.28.27...24.25.26.27.28.29...18.25.24.21.22.29
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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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