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

Author

R. H. Hardin, Oct 22 2015

Keywords

• nonn

Comments

Column 3 of A263643.

Examples

			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
		

Links

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

Crossrefs

Cf. A263643.

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