Journal of Integer Sequences, Vol. 9 (2006), Article 06.3.2

Lattice Path Enumeration of Permutations with k Occurrences of the Pattern 2-13

Robert Parviainen
ARC Centre of Excellence for Mathematics and Statistics of Complex Systems
139 Barry Street
University of Melbourne
Victoria, 3010
Australia

Abstract: We count the number of permutations with k occurrences of the pattern 2-13 in permutations by lattice path enumeration. We give closed forms for k <= 8, extending results of Claesson and Mansour.

(Concerned with sequences A000108 A002696 A094218 A094219 A120812 A120813 A120814 A120815 and A120816 .)

Received July 6 2006; revised version received July 11 2006. Published in Journal of Integer Sequences, July 19 2006.