collaborators

7 papers

math.CO2025

Proper conflict-free degree-choosability of outerplanar graphs

Masaki Kashima, Riste Å krekovski, Rongxing Xu

A proper coloring of is called a proper conflict-free coloring of if for every non-isolated vertex of , there is a color such that $|ϕ^{-1}(c)\cap N_G(v)|=…

math.CO2025

Invitation to the subpath number

Martin Knor, Jelena Sedlar, Riste Å krekovski +1

In this paper we count all the subpaths of a given graph G; including the subpaths of length zero, and we call this quantity the subpath number of G. The subpath number is related…

math.CO2024

Extremizing antiregular graphs by modifying total -irregularity

Martin Knor, Riste Å krekovski, Slobodan Filipovski +1

The total -irregularity is given by where indicates the degree of a vertex within the g…

math.CO2024

On strong odd colorings of graphs

Yair Caro, Mirko Petruševski, Riste Škrekovski +1

A strong odd coloring of a simple graph is a proper coloring of the vertices of such that for every vertex and every color , either is used an odd number of time…

math.CO2024

Normal 5-edge-coloring of some snarks superpositioned by Flower snarks

Jelena Sedlar, Riste Å krekovski

An edge e is normal in a proper edge-coloring of a cubic graph G if the number of distinct colors on four edges incident to e is 2 or 4: A normal edge-coloring of G is a proper edg…

math.CO2024

On regular graphs with Šoltés vertices

Nino Bašić, Martin Knor, Riste Škrekovski

Let be the Wiener index of a graph . We say that a vertex is a Å oltés vertex in if , i.e. the Wiener index does not change if the vert…