June 10, 2023
Doost Ali Mojdeh

Doost Ali Mojdeh

Degree: Professor
Address: Department of Mathematics, University of Mazandaran, Babolsar, Iran
Education: Ph.D in Mathematics (Graph Theory and Combinatorics)
Phone: 011-35302448
Faculty: Faculty of Mathematical Sciences


Title Addendum, The signed bad numbers in graphs
Type Article
Negative decision number; signed bad number; triangle-free graph
Journal Discrete Mathematics, Algorithms and Applications
DOI DOI: 10.1142/S1793830920920019
Researchers Doost Ali Mojdeh (First researcher) , Babak Samadi (Second researcher)


In this paper, we deal with the signed bad number and the negative decision number of graphs. We show that two upper bounds concerning these two parameters for bipartite graphs in papers [Discrete Math. Algorithms Appl. 3 (2011) 33–41] and [Australas. J. Combin. 41 (2008) 263–272] are not true as they stand. We correct them by presenting more general bounds for triangle-free graphs by using the classic theorem of Mantel from extremal graph theory and characterize all triangle-free graphs attaining these bounds.