Results 51 to 60 of about 211 (163)
L(2, 1)-Labelings of Some Families of Oriented Planar Graphs
Discussiones Mathematicae Graph Theory, 2014 In this paper we determine, or give lower and upper bounds on, the 2-dipath and oriented L(2, 1)-span of the family of planar graphs, planar graphs with girth 5, 11, 16, partial k-trees, outerplanar graphs and cacti.
Sen Sagnik
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On an interpolation property of outerplanar graphs
Discrete Applied Mathematics, 2006 Let \(D\) be an acyclic orientation of a graph \(G\). An arc of \(D\) is dependent if a directed cycle is created when it is reversed. Denote by \(d(D)\) the number of dependent arcs in \(D\). Let \(d_{\min}(G)\) be the minimum \(d(D)\), and \(d_{\max}(G)\) the maximum \(d(D)\), over all acyclic orientations \(D\) of \(G\).
Ko-Wei Lih, Chen-Ying Lin, Li-Da Tong
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Nullspace Embeddings for Outerplanar Graphs [PDF]
, 2017 21 pages.
Lovász, L., Schrijver, A.
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Face Sizes and the Connectivity of the Dual
Journal of Graph Theory, Volume 110, Issue 4, Page 379-391, December 2025.ABSTRACT For each c ≥ 1, we prove tight lower bounds on face sizes that must be present to allow 1‐ or 2‐cuts in simple duals of c‐connected maps. Using these bounds, we determine the smallest genus on which a c‐connected map can have a simple dual with a 2‐cut and give lower and some upper bounds for the smallest genus on which a c‐connected map can ...
Gunnar Brinkmann +2 more
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On k-edge-magic labelings of maximal outerplanar graphs
AKCE International Journal of Graphs and Combinatorics, 2015 Let G be a graph with vertex set V and edge set E such that |V|=p and |E|=q. We denote this graph by (p,q)-graph. For integers k≥0, define a one-to-one map f from E to {k,k+1,…,k+q−1} and define the vertex sum for a vertex v as the sum of the labels of ...
Gee-Choon Lau +3 more
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On the spread of outerplanar graphs
Special Matrices, 2022 The spread of a graph is the difference between the largest and most negative eigenvalue of its adjacency matrix. We show that for sufficiently large nn, the nn-vertex outerplanar graph with maximum spread is a vertex joined to a linear forest with Ω(n ...
Gotshall Daniel +2 more
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Recognizing Trees From Incomplete Decks
Journal of Graph Theory, Volume 110, Issue 3, Page 322-336, November 2025.ABSTRACT Given a graph G, the unlabeled subgraphs G − v are called the cards of G. The deck of G is the multiset { G − v : v ∈ V ( G ) }. Wendy Myrvold showed that a disconnected graph and a connected graph both on n vertices have at most ⌊ n 2 ⌋ + 1 cards in common and found (infinite) families of trees and disconnected forests for which this upper ...
Gabriëlle Zwaneveld
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Dichotomy Theorems for Homomorphism Polynomials of Graph Classes
Journal of Graph Algorithms and Applications, 2016 In this paper, we will show dichotomy theorems for the computation of polynomials corresponding to evaluation of graph homomorphisms in Valiant's model. We are given a fixed graph H and want to find all graphs, from some graph class, homomorphic
Christian Engels
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On Endomorphism Universality of Sparse Graph Classes
Journal of Graph Theory, Volume 110, Issue 2, Page 223-244, October 2025.ABSTRACT We show that every commutative idempotent monoid (a.k.a. lattice) is the endomorphism monoid of a subcubic graph. This solves a problem of Babai and Pultr and the degree bound is best‐possible. On the other hand, we show that no class excluding a minor can have all commutative idempotent monoids among its endomorphism monoids. As a by‐product,
Kolja Knauer, Gil Puig i Surroca
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Tight Distance Query Reconstruction for Trees and Graphs Without Long Induced Cycles
Random Structures &Algorithms, Volume 66, Issue 4, July 2025.ABSTRACT Given access to the vertex set V$$ V $$ of a connected graph G=(V,E)$$ G=\left(V,E\right) $$ and an oracle that given two vertices u,v∈V$$ u,v\in V $$, returns the shortest path distance between u$$ u $$ and v$$ v $$, how many queries are needed to reconstruct E$$ E $$?
Paul Bastide, Carla Groenland
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