3 papers
math.CO2025
Subdivisions of Six-Blocks Cycles C(k,1,1,1,1,1) in Strong Digraphs
Hiba Ayoub, Soukaina Zayat, Darine Al-Mniny
A cycle C(k1,k2,...,kn) is the oriented cycle formed of n blocks of lengths k1,k2,...,kn-1 and kn respectively. In 2018 Cohen et al. conjectured that for every positive integers k1…
math.CO2024
About the second neighborhood conjecture for tournaments missing two stars or disjoint paths
Moussa Daamouch, Salman Ghazal, Darine Al-Mniny
Seymour's Second Neighborhood Conjecture (SSNC) asserts that every oriented finite simple graph (without digons) has a vertex whose second out-neighborhood is at least as large as…
math.CO2023
About subdivisions of four blocks cycles in digraphs with large chromatic number
Darine Al-Mniny, Soukaina Zayat
A cycle with four blocks is an oriented cycle formed of four blocks of lengths and respectively. Recently, Cohen et al.…