Mathematics – Combinatorics
Scientific paper
2010-09-12
Mathematics
Combinatorics
16 pages, 4 figures
Scientific paper
The Springer numbers are defined in connection with the irreducible root systems of type $B_n$, which also arise as the generalized Euler and class numbers introduced by Shanks. Combinatorial interpretations of the Springer numbers have been found by Purtill in terms of Andre signed permutations, and by Arnol'd in terms of snakes of type $B_n$. We introduce the inversion code of a snake of type $B_n$ and establish a bijection between labeled ballot paths of length n and snakes of type $B_n$. Moreover, we obtain the bivariate generating function for the number B(n,k) of labeled ballot paths starting at (0,0) and ending at (n,k). Using our bijection, we find a statistic $\alpha$ such that the number of snakes $\pi$ of type $B_n$ with $\alpha(\pi)=k$ equals B(n,k). We also show that our bijection specializes to a bijection between labeled Dyck paths of length 2n and alternating permutations on [2n].
Chen William Y. C.
Fan Neil J. Y.
Jia Jeffrey Y. T.
No associations
LandOfFree
Labeled Ballot Paths and the Springer Numbers 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 Labeled Ballot Paths and the Springer Numbers, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Labeled Ballot Paths and the Springer Numbers will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-326541