{"title":"A note on the metric dimension of subdivided thorn graphs","authors":"L. Yulianti, Narwen Narwen, Sri Hariyani","doi":"10.19184/IJC.2019.3.1.4","DOIUrl":null,"url":null,"abstract":"<p>For some ordered subset <span class=\"math\"><em>W</em> = {<em>w</em><sub>1</sub>, <em>w</em><sub>2</sub>, ⋯, <em>w</em><sub><em>t</em></sub>}</span> of vertices in connected graph <span class=\"math\"><em>G</em></span>, and for some vertex <span class=\"math\"><em>v</em></span> in <span class=\"math\"><em>G</em></span>, the metric representation of <span class=\"math\"><em>v</em></span> with respect to <span class=\"math\"><em>W</em></span> is defined as the <span class=\"math\"><em>t</em></span>-vector <span class=\"math\"><em>r</em>(<em>v</em>∣<em>W</em>) = {<em>d</em>(<em>v</em>, <em>w</em><sub>1</sub>), <em>d</em>(<em>v</em>, <em>w</em><sub>2</sub>), ⋯, <em>d</em>(<em>v</em>, <em>w</em><sub><em>t</em></sub>)}</span>. The set <span class=\"math\"><em>W</em></span> is the resolving set of <span class=\"math\"><em>G</em></span> if for every two vertices <span class=\"math\"><em>u</em>, <em>v</em></span> in <span class=\"math\"><em>G</em></span>, <span class=\"math\"><em>r</em>(<em>u</em>∣<em>W</em>) ≠ <em>r</em>(<em>v</em>∣<em>W</em>)</span>. The metric dimension of <span class=\"math\"><em>G</em></span>, denoted by <span class=\"math\">dim(<em>G</em>)</span>, is defined as the minimum cardinality of <span class=\"math\"><em>W</em></span>. Let <span class=\"math\"><em>G</em></span> be a connected graph on <span class=\"math\"><em>n</em></span> vertices. The thorn graph of <span class=\"math\"><em>G</em></span>, denoted by <span class=\"math\"><em>T</em><em>h</em>(<em>G</em>, <em>l</em><sub>1</sub>, <em>l</em><sub>2</sub>, ⋯, <em>l</em><sub><em>n</em></sub>)</span>, is constructed from <span class=\"math\"><em>G</em></span> by adding <span class=\"math\"><em>l</em><sub><em>i</em></sub></span> leaves to vertex <span class=\"math\"><em>v</em><sub><em>i</em></sub></span> of <span class=\"math\"><em>G</em></span>, for <span class=\"math\"><em>l</em><sub><em>i</em></sub> ≥ 1</span> and <span class=\"math\">1 ≤ <em>i</em> ≤ <em>n</em></span>. The subdivided-thorn graph, denoted by <span class=\"math\"><em>T</em><em>D</em>(<em>G</em>, <em>l</em><sub>1</sub>(<em>y</em><sub>1</sub>), <em>l</em><sub>2</sub>(<em>y</em><sub>2</sub>), ⋯, <em>l</em><sub><em>n</em></sub>(<em>y</em><sub><em>n</em></sub>))</span>, is constructed by subdividing every <span class=\"math\"><em>l</em><sub><em>i</em></sub></span> leaves of the thorn graph of <span class=\"math\"><em>G</em></span> into a path on <span class=\"math\"><em>y</em><sub><em>i</em></sub></span> vertices. In this paper the metric dimension of thorn of complete graph, <span class=\"math\">dim(<em>T</em><em>h</em>(<em>K</em><sub><em>n</em></sub>, <em>l</em><sub>1</sub>, <em>l</em><sub>2</sub>, ⋯, <em>l</em><sub><em>n</em></sub>))</span>, <span class=\"math\"><em>l</em><sub><em>i</em></sub> ≥ 1</span> are determined, partially answering the problem proposed by Iswadi et al . This paper also gives some conjectures for the lower bound of <span class=\"math\">dim(<em>T</em><em>h</em>(<em>G</em>, <em>l</em><sub>1</sub>, <em>l</em><sub>2</sub>, ⋯, <em>l</em><sub><em>n</em></sub>))</span>, for arbitrary connected graph <span class=\"math\"><em>G</em></span>. Next, the metric dimension of subdivided-thorn of complete graph, <span class=\"math\">dim(<em>T</em><em>D</em>(<em>K</em><sub><em>n</em></sub>, <em>l</em><sub>1</sub>(<em>y</em><sub>1</sub>), <em>l</em><sub>2</sub>(<em>y</em><sub>2</sub>), ⋯, <em>l</em><sub><em>n</em></sub>(<em>y</em><sub><em>n</em></sub>))</span> are determined and some conjectures for the lower bound of <span class=\"math\">dim(<em>T</em><em>h</em>(<em>G</em>, <em>l</em><sub>1</sub>(<em>y</em><sub>1</sub>), <em>l</em><sub>2</sub>(<em>y</em><sub>2</sub>), ⋯, <em>l</em><sub><em>n</em></sub>(<em>y</em><sub><em>n</em></sub>))</span> for arbitrary connected graph <span class=\"math\"><em>G</em></span> are given.</p>","PeriodicalId":13506,"journal":{"name":"Indonesian Journal of Combinatorics","volume":"19 1","pages":""},"PeriodicalIF":0.0000,"publicationDate":"2019-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"1","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Indonesian Journal of Combinatorics","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.19184/IJC.2019.3.1.4","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 1
Abstract
For some ordered subset W = {w1, w2, ⋯, wt} of vertices in connected graph G, and for some vertex v in G, the metric representation of v with respect to W is defined as the t-vector r(v∣W) = {d(v, w1), d(v, w2), ⋯, d(v, wt)}. The set W is the resolving set of G if for every two vertices u, v in G, r(u∣W) ≠ r(v∣W). The metric dimension of G, denoted by dim(G), is defined as the minimum cardinality of W. Let G be a connected graph on n vertices. The thorn graph of G, denoted by Th(G, l1, l2, ⋯, ln), is constructed from G by adding li leaves to vertex vi of G, for li ≥ 1 and 1 ≤ i ≤ n. The subdivided-thorn graph, denoted by TD(G, l1(y1), l2(y2), ⋯, ln(yn)), is constructed by subdividing every li leaves of the thorn graph of G into a path on yi vertices. In this paper the metric dimension of thorn of complete graph, dim(Th(Kn, l1, l2, ⋯, ln)), li ≥ 1 are determined, partially answering the problem proposed by Iswadi et al . This paper also gives some conjectures for the lower bound of dim(Th(G, l1, l2, ⋯, ln)), for arbitrary connected graph G. Next, the metric dimension of subdivided-thorn of complete graph, dim(TD(Kn, l1(y1), l2(y2), ⋯, ln(yn)) are determined and some conjectures for the lower bound of dim(Th(G, l1(y1), l2(y2), ⋯, ln(yn)) for arbitrary connected graph G are given.