3 papers
math.CO2025
A bijection between - and -avoiding permutations preserving -stack-sortability
Yang Li, Sergey Kitaev, Zhicong Lin +1
We construct a bijection between - and -avoiding permutations that preserves the property of -stack-sortability. Our bijection transforms natural statistics between th…
math.CO2025
Bijections in weakly increasing trees via binary trees
Yang Li, Zhicong Lin
As a unification of increasing trees and plane trees, the weakly increasing trees labeled by a multiset was introduced by Lin-Ma-Ma-Zhou in 2021. Motived by some symmetries in plan…
math.CO2024
Bijections around Springer numbers
Shaoshi Chen, Yang Li, Zhicong Lin +1
Arnol'd proved in 1992 that Springer numbers enumerate the Snakes, which are type analogs of alternating permutations. Chen, Fan and Jia in 2011 introduced the labeled ballot p…