activity
20112025
most cited3-coloring triangle-free planar graphs with a precolored 9-cycle

5 citations · 5 across the 5 of their papers we have counts for

collaborators
Showing 2017Show all

2 papers · 1 filter

math.CO2017★ 5 cited

3-coloring triangle-free planar graphs with a precolored 9-cycle

Ilkyoo Choi, Jan Ekstein, Přemysl Holub +1

Given a triangle-free planar graph G and a 9-cycle C in G, we characterize situations where a 3-coloring of C does not extend to a proper 3-coloring of G. This extends previous res…

math.CO2017

Revisiting the Hamiltonian Theme in the Square of a Block: The Case of DT-Graphs

Gek L. Chia, Jan Ekstein, Herbert Fleischner

The square of a graph G, denoted G^2, is the graph obtained from G by joining by an edge any two nonadjacent vertices which have a common neighbor. A graph G is said to have the F_…