Let D = (V,A) be a finite simple directed graph (shortly, digraph). A function f : V → {−1, 0, 1} is called a twin minus total dominating function (TMTDF) if f(N−(v)) ≥ 1 and f(N+(v)) ≥ 1 for each vertex v ∈ V. The twin minus total domination number of D is y*mt(D) = min{w(f) | f is a TMTDF of D}. In this paper, we initiate the study of twin minus total domination numbers in digraphs and we present some lower bounds for y*mt(D) in terms of the order, size and maximum and minimum in-degrees and out-degrees. In addition, we determine the twin minus total domination numbers of some classes of digraphs.
@article{bwmeta1.element.doi-10_7151_dmgt_1983, author = {Nasrin Dehgardi and Maryam Atapour}, title = {Twin Minus Total Domination Numbers In Directed Graphs}, journal = {Discussiones Mathematicae Graph Theory}, volume = {37}, year = {2017}, pages = {989-1004}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.doi-10_7151_dmgt_1983} }
Nasrin Dehgardi; Maryam Atapour. Twin Minus Total Domination Numbers In Directed Graphs. Discussiones Mathematicae Graph Theory, Tome 37 (2017) pp. 989-1004. http://gdmltest.u-ga.fr/item/bwmeta1.element.doi-10_7151_dmgt_1983/