3 papers
cs.DS2026
An FPT algorithm for cycle rank on semi-complete digraphs
Seokbeom Kim, O-joung Kwon, Myounghwan Lee
Cycle rank is a depth parameter for digraphs introduced by Eggan in 1963. Gruber (DMTCS 2012) and Giannopoulou, Hunter, and Thilikos (DAM 2012) asked whether the problem of determi…
math.CO2025
Unavoidable butterfly minors in digraphs of large cycle rank
Meike Hatzel, O-joung Kwon, Myounghwan Lee +1
Cycle rank is one of the depth parameters for digraphs introduced by Eggan in 1963. We show that there exists a function such that every digraph of cyc…
math.CO2019
Graphs without two vertex-disjoint -cycles
Minjeong Kang, O-joung Kwon, Myounghwan Lee
Lovász (1965) characterized graphs without two vertex-disjoint cycles, which implies that such graphs have at most three vertices hitting all cycles. In this paper, we ask whether…