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Related papers: A Steiner general position problem in graph theory

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The Wiener index W(G) of a graph G is the sum of distances between all unordered pairs of its vertices. Dobrynin and Mel'nikov [in: Distance in Molecular Graphs - Theory, 2012, p. 85-121] propose the study of estimates for extremal values…

Combinatorics · Mathematics 2024-01-24 Mohammad Ghebleh , Ali Kanso

The Steiner $k$-diameter $sdiam_k(G)$ of a graph $G$, introduced by Chartrand, Oellermann, Tian and Zou in 1989, is a natural generalization of the concept of classical diameter. When $k=2$, $sdiam_2(G)=diam(G)$ is the classical diameter.…

Combinatorics · Mathematics 2019-08-19 Yaping Mao

The general $d$-position number ${\rm gp}_d(G)$ of a graph $G$ is the cardinality of a largest set $S$ for which no three distinct vertices from $S$ lie on a common geodesic of length at most $d$. This new graph parameter generalizes the…

Combinatorics · Mathematics 2020-05-19 Sandi Klavzar , Douglas F. Rall , Ismael G. Yero

We propose polynomial-time algorithms that sparsify planar and bounded-genus graphs while preserving optimal or near-optimal solutions to Steiner problems. Our main contribution is a polynomial-time algorithm that, given an unweighted graph…

Data Structures and Algorithms · Computer Science 2017-07-12 Marcin Pilipczuk , Michał Pilipczuk , Piotr Sankowski , Erik Jan van Leeuwen

A circle graph is an intersection graph of a set of chords of a circle. We describe the unavoidable induced subgraphs of circle graphs with large treewidth. This includes examples that are far from the `usual suspects'. Our results imply…

Combinatorics · Mathematics 2022-12-23 Robert Hickingbotham , Freddie Illingworth , Bojan Mohar , David R. Wood

The edge geodesic cover problem of a graph $G$ is to find a smallest number of geodesics that cover the edge set of $G$. The edge $k$-general position problem is introduced as the problem to find a largest set $S$ of edges of $G$ such that…

Combinatorics · Mathematics 2022-07-18 Paul Manuel , R. Prabha , Sandi Klavzar

Let $T$ be a distinguished subset of vertices in a graph $G$. A $T$-\emph{Steiner tree} is a subgraph of $G$ that is a tree and that spans $T$. Kriesell conjectured that $G$ contains $k$ pairwise edge-disjoint $T$-Steiner trees provided…

Combinatorics · Mathematics 2015-08-11 Matt DeVos , Jessica McDonald , Irene Pivotto

The general position number ${\rm gp}(G)$ of a graph $G$ is the cardinality of a largest set of vertices $S$ such that no element of $S$ lies on a geodesic between two other elements of $S$. The complementary prism $G\overline{G}$ of $G$ is…

Combinatorics · Mathematics 2020-01-08 Neethu P. K. , Ullas Chandran S. V. , Manoj Changat , Sandi Klavžar

If $G$ is a graph, then $X\subseteq V(G)$ is a general position set if for every two vertices $v,u\in X$ and every shortest $(u,v)$-path $P$, it holds that no inner vertex of $P$ lies in $X$. In this note we propose three algorithms to…

Combinatorics · Mathematics 2026-01-14 Zahra Hamed-Labbafian , Narjes Sabeghi , Mostafa Tavakoli , Sandi Klavžar

The general position number of a connected graph is the cardinality of a largest set of vertices such that no three pairwise-distinct vertices from the set lie on a common shortest path. In this paper it is proved that the general position…

Combinatorics · Mathematics 2023-06-22 Jing Tian , Kexiang Xu , Sandi Klavžar

For an ordered set $W=\{w_1,w_2,...,w_k\}$ of vertices and a vertex $v$ in a connected graph $G$, the ordered $k$-vector $r(v|W):=(d(v,w_1),d(v,w_2),...,d(v,w_k))$ is called the (metric) representation of $v$ with respect to $W$, where…

Combinatorics · Mathematics 2011-03-17 Mohsen Jannesari , Behnaz Omoomi

The Euclidean Steiner problem is the problem of finding a set $St$, with the shortest length, such that $St \cup A$ is connected, where $A$ is a given set in a Euclidean space. The solutions $St$ to the Steiner problem will be called…

Metric Geometry · Mathematics 2025-02-20 Danila Cherkashin , Emanuele Paolini , Yana Teplitskaya

Given a directed graph G and an integer k >= 1, a k-transitive-closure-spanner (k-TCspanner) of G is a directed graph H that has (1) the same transitive-closure as G and (2) diameter at most k. In some applications, the shortcut paths added…

Data Structures and Algorithms · Computer Science 2010-11-30 Piotr Berman , Arnab Bhattacharyya , Elena Grigorescu , Sofya Raskhodnikova , David Woodruff , Grigory Yaroslavtsev

Given a simple connected undirected graph G, the Wiener index W(G) of G is defined as half the sum of the distances over all pairs of vertices of G. In practice, G corresponds to what is known as the molecular graph of an organic compound.…

Discrete Mathematics · Computer Science 2010-12-13 R. Balakrishnan , N. Sridharan , K. V. Iyer

Let $G \otimes _f H$ denote the Sierpi\'nski product of graphs $G$ and $H$ with respect to the function $f$. The Sierpi\'nski general position number ${\rm gp}{_{\rm S}}(G,H)$ is introduced as the cardinality of a largest general position…

Combinatorics · Mathematics 2025-12-10 Sandi Klavžar , Jing Tian

Given an undirected graph $G = (V, E)$ and a weight function $w:E \to \mathbb{R}$, the \textsc{Minimum Dominating Tree} problem asks to find a minimum weight sub-tree of $G$, $T = (U, F)$, such that every $v \in V \setminus U$ is adjacent…

Computational Complexity · Computer Science 2018-02-14 Gilad Kutiel

A formula based on a vertex contributions of the Steiner $k$-Wiener index is induced by a newly introduced $k$-Steiner betweenness centrality, which measures the number of $k$-Steiner trees that include a particular vertex as a non-terminal…

Combinatorics · Mathematics 2016-05-11 Matjaž Kovše

With applications in distribution systems and communication networks, the minimum stretch spanning tree problem is to find a spanning tree T of a graph G such that the maximum distance in T between two adjacent vertices is minimized. The…

Combinatorics · Mathematics 2017-12-12 Lan Lin , Yixun Lin

We study the problem of constructing universal Steiner trees for undirected graphs. Given a graph $G$ and a root node $r$, we seek a single spanning tree $T$ of minimum {\em stretch}, where the stretch of $T$ is defined to be the maximum…

Data Structures and Algorithms · Computer Science 2015-03-03 Costas Busch , Chinmoy Dutta , Jaikumar Radhakrishnan , Rajmohan Rajaraman , Srivathsan Srinivasagopalan

Let $G = (V,E)$ be a graph and $k \ge 0$ an integer. A $k$-independent set $S \subseteq V$ is a set of vertices such that the maximum degree in the graph induced by $S$ is at most $k$. With $\alpha_k(G)$ we denote the maximum cardinality of…

Combinatorics · Mathematics 2012-08-24 Yair Caro , Adriana Hansberg