Mathematics – Combinatorics
Scientific paper
2002-05-20
Mathematics
Combinatorics
18 pages
Scientific paper
Babson and Steingr\'{\i}msson introduced generalized permutation patterns that allow the requirement that two adjacent letters in a pattern must be adjacent in the permutation. We consider n-permutations that avoid the generalized pattern 1-32 and whose k rightmost letters form an increasing subword. The number of such permutations is a linear combination of Bell numbers. We find a bijection between these permutations and all partitions of an $(n-1)$-element set with one subset marked that satisfy certain additional conditions. Also we find the e.g.f. for the number of permutations that avoid a generalized 3-pattern with no dashes and whose k leftmost or k rightmost letters form either an increasing or decreasing subword. Moreover, we find a bijection between n-permutations that avoid the pattern 132 and begin with the pattern 12 and increasing rooted trimmed trees with n+1 nodes.
No associations
LandOfFree
Generalized pattern avoidance with additional restrictions does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Generalized pattern avoidance with additional restrictions, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Generalized pattern avoidance with additional restrictions will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-242552