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A263699
Number of length n arrays of permutations of 0..n-1 with each element moved by -4 to 4 places and every three consecutive elements having its maximum within 4 of its minimum.
1
1, 2, 6, 24, 120, 168, 204, 348, 696, 1601, 3476, 7244, 14048, 27164, 54300, 109741, 223641, 452621, 908389, 1822758, 3657710, 7359642, 14825163, 29845108, 60064056, 120806672, 242986234, 488854773, 983578792, 1979138437, 3982088115
OFFSET
1,2
COMMENTS
Column 4 of A263703.
LINKS
FORMULA
Empirical: a(n) = a(n-1) +a(n-2) +7*a(n-5) +2*a(n-6) +a(n-7) +5*a(n-8) -4*a(n-9) -3*a(n-10) -3*a(n-11) -4*a(n-12) -4*a(n-14) -a(n-15) +3*a(n-16) -a(n-17) +a(n-19) for n>27
EXAMPLE
Some solutions for n=7
..1....1....0....3....0....1....0....0....2....1....0....0....2....1....1....3
..0....0....3....1....4....0....4....1....0....2....1....2....3....3....0....0
..4....3....1....0....1....4....1....3....1....0....3....1....0....0....2....2
..2....2....4....2....2....3....2....5....3....3....2....4....1....4....3....1
..6....5....2....4....5....2....3....6....5....4....4....5....4....2....6....4
..3....4....6....5....3....5....6....4....6....5....5....6....5....5....4....5
..5....6....5....6....6....6....5....2....4....6....6....3....6....6....5....6
CROSSREFS
Cf. A263703.
Sequence in context: A190393 A263709 A279435 * A083267 A130480 A000804
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 24 2015
STATUS
approved