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A263638
Number of length n arrays of permutations of 0..n-1 with each element moved by -3 to 3 places and with no two consecutive increases.
1
1, 2, 5, 17, 41, 75, 156, 340, 738, 1567, 3327, 7136, 15258, 32589, 69621, 148780, 317987, 679467, 1451887, 3102670, 6630039, 14167934, 30275260, 64695775, 138248719, 295425310, 631295545, 1349022959, 2882734510, 6160146104
OFFSET
1,2
COMMENTS
Column 3 of A263643.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-2) +2*a(n-3) +3*a(n-4) +2*a(n-5) -2*a(n-6) -6*a(n-7) +2*a(n-8) -4*a(n-9) -2*a(n-10) +3*a(n-11) -2*a(n-12) +a(n-14) for n>19
EXAMPLE
Some solutions for n=6
..2....2....1....2....3....3....0....1....1....3....0....2....1....1....2....1
..0....3....0....4....1....0....4....3....3....1....4....3....0....4....4....4
..4....0....5....0....0....5....1....0....2....0....2....0....5....2....1....0
..1....5....3....3....5....1....5....4....0....4....5....4....2....0....0....3
..5....1....2....1....2....4....2....2....5....2....1....1....4....5....5....2
..3....4....4....5....4....2....3....5....4....5....3....5....3....3....3....5
CROSSREFS
Cf. A263643.
Sequence in context: A320102 A197918 A122566 * A118500 A323427 A080898
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 22 2015
STATUS
approved