9 papers
Triangle-free projective-planar graphs with diameter two: domination and characterization
Dibyayan Chakraborty, Sandip Das, Srijit Mukherjee +2
In 1975, Plesník characterized all triangle-free planar graphs as having a diameter . We characterize all triangle-free projective-planar graphs having a diameter and discus…
On fractional version of oriented coloring
Sandip Das, Soham Das, Swathy Prabhu +1
We introduce the fractional version of oriented coloring and initiate its study. We prove some basic results and study the parameter for directed cycles and sparse planar graphs. I…
On subgraph complementation to H-free graphs
Dhanyamol Antony, Jay Garchar, Sagartanu Pal +3
For a class of graphs, the problem SUBGRAPH COMPLEMENT TO asks whether one can find a subset of vertices of the input graph such that complement…
On the signed chromatic number of some classes of graphs
Julien Bensmail, Sandip Das, Soumen Nandi +3
A signed graph is a graph along with a function . A closed walk of a signed graph is positive (resp., negative) if it has an even (resp., odd) num…
Pushable chromatic number of graphs with degree constraints
Julien Bensmail, Sandip Das, Soumen Nandi +4
Pushable homomorphisms and the pushable chromatic number of oriented graphs were introduced by Klostermeyer and MacGillivray in 2004. They notably observed that, for any orie…
On relative clique number of colored mixed graphs
Sandip Das, Soumen Nandi, Debdeep Roy +1
An -colored mixed graph is a graph having arcs of different colors and edges of different colors. A graph homomorphism of an )-colored mixed graph to an…