Results 121 to 130 of about 63,637 (247)
Outer independent total double Italian domination number [PDF]
Computer Science Journal of MoldovaIf $G$ is a graph with vertex set $V(G)$, then let $N[u]$ be the closed neighborhood of the vertex $u\in V(G)$. A total double Italian dominating function (TDIDF) on a graph $G$ is a function $f:V(G)\rightarrow\{0,1,2,3\}$ satisfying (i) $f(N[u])\ge 3 ...
Seyed Mahmoud Sheikholeslami +1 more
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A Sharper Ramsey Theorem for Constrained Drawings
Journal of Graph Theory, Volume 109, Issue 4, Page 401-411, August 2025.ABSTRACT Given a graph G and a collection C of subsets of R d indexed by the subsets of vertices of G, a constrained drawing of G is a drawing where each edge is drawn inside some set from C, in such a way that nonadjacent edges are drawn in sets with disjoint indices. In this paper we prove a Ramsey‐type result for such drawings.
Pavel Paták
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Edge‐Connectivity Between Edge‐Ends of Infinite Graphs
Journal of Graph Theory, Volume 109, Issue 4, Page 454-465, August 2025.ABSTRACT In infinite graph theory, the notion of ends, first introduced by Freudenthal and Jung for locally finite graphs, plays an important role when generalizing statements from finite graphs to infinite ones. Nash‐Williams' Tree‐Packing Theorem and MacLane's Planarity Criteria are examples of results that allow a topological approach, in which ends
Leandro Aurichi, Lucas Real
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On 3-Colorings of Direct Products of Graphs
Discussiones Mathematicae Graph Theory, 2019 The k-independence number of a graph G, denoted as αk(G), is the order of a largest induced k-colorable subgraph of G. In [S. Špacapan, The k-independence number of direct products of graphs, European J. Combin.
Špacapan Simon
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The Generic Circular Triangle‐Free Graph
Journal of Graph Theory, Volume 109, Issue 4, Page 426-445, August 2025.ABSTRACT In this article, we introduce the generic circular triangle‐free graph C 3 and propose a finite axiomatization of its first‐order theory. In particular, our main results show that a countable graph G embeds into C 3 if and only if it is a { K 3 , K 1 + 2 K 2 , K 1 + C 5 , C 6 }‐free graph.
Manuel Bodirsky, Santiago Guzmán‐Pro
wiley +1 more source
Note on Hamiltonicity of Basis Graphs of Even Delta‐Matroids
Journal of Graph Theory, Volume 109, Issue 4, Page 446-453, August 2025.ABSTRACT We show that the basis graph of an even delta‐matroid is Hamiltonian if it has more than two vertices. More strongly, we prove that for two distinct edges e and f sharing a common end, it has a Hamiltonian cycle using e and avoiding f unless it has at most two vertices or it is a cycle of length at most four.
Donggyu Kim, Sang‐il Oum
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On the number of induced subgraphs of trees
Discrete Mathematics, 1997 Abstract Baron and Drmota (1993) used generating functions to obtain explicit formulas for the number of induced subgraphs with components of given sizes contained in trees Tn belonging to three particular families of trees. Using a different approach, we derive a more general result that contains their formulas as special cases.
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Conformal Hypergraphs: Duality and Implications for the Upper Clique Transversal Problem
Journal of Graph Theory, Volume 109, Issue 4, Page 466-480, August 2025.ABSTRACT Given a hypergraph ℋ, the dual hypergraph of ℋ is the hypergraph of all minimal transversals of ℋ. The dual hypergraph is always Sperner, that is, no hyperedge contains another. A special case of Sperner hypergraphs are the conformal Sperner hypergraphs, which correspond to the families of maximal cliques of graphs.
Endre Boros +3 more
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An induced subgraph characterization of domination perfect graphs [PDF]
, 1995 Igor E. Zvervich, Vadim Zverovich
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