3 papers
math.CO2026
Bijections between pattern-avoiding derangements and desarrangements
Alyssa G. Henke, Derek H. Stephens, Yan Zhuang
Derangements are permutations without fixed points, and are in bijection with desarrangements: permutations whose first non-descent is even, or equivalently, permutations without `…
math.CO2024
Counting pattern-avoiding permutations by big descents
Sergi Elizalde, Johnny Rivera, Yan Zhuang
A descent of a permutation is called a big descent if ; denote the number of big descents of by . We study…
cs.DS2024
BFS versus DFS for fixed-level targets in ordered trees
Stoyan Dimitrov, Martin Minchev, Yan Zhuang
We find the average time complexity of the breadth-first search (BFS) and the depth-first search (DFS) algorithms, when one searches for a target node selected uniformly at random…