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, 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

R. H. Hardin, Table of n, a(n) for n = 1..210

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

Adjacent sequences: A263635 A263636 A263637 * A263639 A263640 A263641

Keyword

nonn

Author

R. H. Hardin, Oct 22 2015

Status

approved