Lower and upper bounds on independent double Roman domination in trees
Main Authors: | Kheibari, M.; Department of Mathematics, Azarbaijan Shahid Madani University, Tabriz, Iran, Abdollahzadeh Ahangar, Hossein; Department of Mathematics, Babol Noshirvani University of Technology, Shariati Ave., Babol, I.R. Iran, Khoeilar, R.; Department of Mathematics, Azarbaijan Shahid Madani University, Tabriz, Iran, Sheikholeslami, S.M.; Department of Mathematics, Azarbaijan Shahid Madani University, Tabriz, Iran |
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Other Authors: | H. Abdollahzadeh Ahangar, Babol Noshirvani University of Technology, Department of Mathematics, under research grant number BNUT/385001/00 |
Format: | Article info application/pdf eJournal |
Bahasa: | eng |
Terbitan: |
GTA Research Group, Univ. Newcastle, Indonesian Combinatorics Society and ITB
, 2022
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Subjects: | |
Online Access: |
https://www.ejgta.org/index.php/ejgta/article/view/1334 https://www.ejgta.org/index.php/ejgta/article/view/1334/pdf_249 |
Daftar Isi:
- For a graph G = (V, E), a double Roman dominating function (DRDF) f : V → {0, 1, 2, 3} has the property that for every vertex v ∈ V with f(v)=0, either there exists a neighbor u ∈ N(v), with f(u)=3, or at least two neighbors x, y ∈ N(v) having f(x)=f(y)=2, and every vertex with value 1 under f has at least a neighbor with value 2 or 3. The weight of a DRDF is the sum f(V)=∑v ∈ Vf(v). A DRDF f is an independent double Roman dominating function (IDRDF) if the vertices with weight at least two form an independent set. The independent double Roman domination number idR(G) is the minimum weight of an IDRDF on G. In this paper, we show that for every tree T with diameter at least three, i(T)+iR(T)−(s(T))/2 + 1 ≤ idR(T)≤i(T)+iR(T)+s(T)−2, where i(T),iR(T) and s(T) are the independent domination number, the independent Roman domination number and the number of support vertex of T, respectively.