
arXiv: 2108.04302
Motivated by the study of pattern avoidance in the context of permutations and ordered partitions, we consider the enumeration of weak-ordering chains obtained as leaves of certain restricted rooted trees. A tree of order $n$ is generated by inserting a new variable into each node at every step. A node becomes a leaf either after $n$ steps or when a certain stopping condition is met. In this paper we focus on conditions of size 2 ($x=y$, $x<y$, or $x\le y$) and several conditions of size 3. Some of the cases considered here lead to the study of descent statistics of certain `almost' pattern-avoiding permutations.
Permutations, words, matrices, weak orderings, mathematics - combinatorics, Exact enumeration problems, generating functions, Trees, Combinatorics of partially ordered sets, 05A18, pattern avoidance, Partitions of sets, 05a18, QA1-939, generating trees, FOS: Mathematics, Mathematics - Combinatorics, Combinatorics (math.CO), Mathematics
Permutations, words, matrices, weak orderings, mathematics - combinatorics, Exact enumeration problems, generating functions, Trees, Combinatorics of partially ordered sets, 05A18, pattern avoidance, Partitions of sets, 05a18, QA1-939, generating trees, FOS: Mathematics, Mathematics - Combinatorics, Combinatorics (math.CO), Mathematics
| selected citations These citations are derived from selected sources. This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | 0 | |
| popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network. | Average | |
| influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | Average | |
| impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network. | Average |
