Results 31 to 40 of about 7,928 (143)

Hypergraph Anti‐Ramsey Theorems

Journal of Graph Theory
ABSTRACTThe anti‐Ramsey number of an ‐graph is the minimum number of colors needed to color the complete ‐vertex ‐graph to ensure the existence of a rainbow copy of . We establish a removal‐type result for the anti‐Ramsey problem of when is the expansion of a hypergraph with a smaller uniformity. We present two applications of this result.
Xizhi Liu, Jialei Song
openaire   +2 more sources

Approximating Maximum Edge 2-Coloring by Normalizing Graphs [PDF]

Discrete Mathematics & Theoretical Computer Science
In a simple, undirected graph G, an edge 2-coloring is a coloring of the edges such that no vertex is incident to edges with more than 2 distinct colors.
Tobias Mömke, Alexandru Popa, Aida Roshany-Tabrizi, Michael Ruderer, Roland Vincze   +4 more
doaj   +1 more source

Anti-Ramsey Number of Matchings in 3-Uniform Hypergraphs

SIAM Journal on Discrete Mathematics, 2023
Let $n,s,$ and $k$ be positive integers such that $k\geq 3$, $s\geq 3$ and $n\geq ks$. An $s$-matching $M_s$ in a $k$-uniform hypergraph is a set of $s$ pairwise disjoint edges. The anti-Ramsey number $\textrm{ar}(n,k,M_s)$ of an $s$-matching is the smallest integer $c$ such that each edge-coloring of the $n$-vertex $k$-uniform complete hypergraph with
Guo, Mingyang, Lu, Hongliang, Peng, Xing
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Anti-Ramsey Numbers for Graphs with Independent Cycles [PDF]

The Electronic Journal of Combinatorics, 2009
An edge-colored graph is called rainbow if all the colors on its edges are distinct. Let ${\cal G}$ be a family of graphs. The anti-Ramsey number $AR(n,{\cal G})$ for ${\cal G}$, introduced by Erdős et al., is the maximum number of colors in an edge coloring of $K_n$ that has no rainbow copy of any graph in ${\cal G}$. In this paper, we determine the
Jin, Zemin, Li, Xueliang
openaire   +2 more sources

Almost-Rainbow Edge-Colorings of Some Small Subgraphs

Discussiones Mathematicae Graph Theory, 2013
Let f(n, p, q) be the minimum number of colors necessary to color the edges of Kn so that every Kp is at least q-colored. We improve current bounds on these nearly “anti-Ramsey” numbers, first studied by Erdös and Gyárfás.
Krop Elliot, Krop Irina
doaj   +1 more source

Effect of Time to Start of Biologic Therapy on Treatment Response in Childhood Arthritis: Results From the UCAN CAN‐DU Cohort

Arthritis &Rheumatology, EarlyView.
Objective To estimate the effect of time from symptom onset to start of biologic treatment on achieving inactive arthritis within six months in a cohort of patients with juvenile idiopathic arthritis (JIA). Methods The international UCAN CAN‐DU study prospectively enrolled patients with JIA across Canada and the Netherlands.
Jelleke B. de Jonge, Sytze de Roock, Dieneke Schonenberg‐Meinema, J. Merlijn van den Berg, Deborah A. Marshall, Sebastiaan J. Vastert, Rae S. M. Yeung, Joost F. Swart, Susanne M. Benseler, on behalf of the UCAN CAN‐DU and UCAN CURE consortia, Adam Huber, Bianca Lang, Chelsea DeCoste, Elizabeth Stringer, Suzanne Ramsey, Alan Rosenberg, Kate Neufeld, Mehul Jariwala, Tristan Kerr, Alexander Mosoiu, Alisa Rachlis, Amy Xu, Arthur Cheng, Brenleigh Jebb, Brian Feldman, Bruno Pereira, Deborah Levy, Dilan Dissanayake, Elizaveta Limenis, Evelyn Rozenblyum, Harper Cheng, Jennifer Ji Young Lee, Lynn Spiegel, Rayfel Schneider, Ronald Laxer, Ruud Verstegen, Shirley Tse, Trang Duong, Andrea Human, David Cabral, Herman Tam, Jaime Guzman, Kim Morishita, Kristin Houghton, Lori Tucker, Mercedes Chan, Ross Petty, Tommy Gerschman, Annet van Royen‐Kerkhof, Berent Prakken, Erika Van Nieuwenhove, Marc Jansen, Nico Wulffraat, Ciarán Duffy, Nadia Luca, Roman Jurencak, Tala El Tal, Claire LeBlanc, Gaëlle Chédeville, Piya Lahiry, Rosie Scuccimarri, Sarah Campillo, Clare Hutchinson, Daniah Basodan, Dax G. Rumsey, Hon Yan Ng, Jeanine McColl, Lillian Lim, Tara McGrath, Danielle Brinkman, Petra Hissink Muller, Elizabeth Legger, Wineke Armbrust, Ellen Schatorje, Esther Hoppenreijs, Elodie Boudes, Gillian Currie, Heinrike Schmeling, Muhammed Dhalla, Nicole Johnson, Paivi Miettunen, Ravneet Sran, Rebeka Stevenson, Erkan Demirkaya, Jonathan Park, Roberta Berard, Giske Biesbroek, Mariken Gruppen, Gordon Soon, Joseph Cafazzo, Liane Heale, Michelle Batthish, Tania Cellucci, Lily Lim, Maarten IJzerman, Marinka Twilt, Marleen Verkaaik, Philomine van Pelt, Sylvia Kamphuis, Michelle Kip, Nickolas Blanchette, Paul Dancey, Regina de Geus   +102 more
wiley   +1 more source

On the heterochromatic number of hypergraphs associated to geometric graphs and to matroids

, 2010
The heterochromatic number hc(H) of a non-empty hypergraph H is the smallest integer k such that for every colouring of the vertices of H with exactly k colours, there is a hyperedge of H all of whose vertices have different colours.
A. García, Eduardo Rivera-Campo, G. Károlyi, J. Arocha, Juan José Montellano-Ballesteros, T. Jiang, V. Voloshin   +6 more
core   +1 more source

On degree anti-Ramsey numbers

European Journal of Combinatorics, 2017
The degree anti-Ramsey number $AR_d(H)$ of a graph $H$ is the smallest integer $k$ for which there exists a graph $G$ with maximum degree at most $k$ such that any proper edge colouring of $G$ yields a rainbow copy of $H$. In this paper we prove a general upper bound on degree anti-Ramsey numbers, determine the precise value of the degree anti-Ramsey ...
Gilboa, Shoni, Hefetz, Dan
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Anti-Ramsey numbers for vertex-disjoint triangles

Discrete Mathematics, 2023
An edge-colored graph is called rainbow if all the colors on its edges are distinct. Given a positive integer n and a graph G, the anti-Ramsey number ar(n,G) is the maximum number of colors in an edge-coloring of K_{n} with no rainbow copy of G. Denote by kC_{3} the union of k vertex-disjoint copies of C_{3}. In this paper, we determine the anti-Ramsey
Fangfang Wu, Shenggui Zhang, Binlong Li, Jimeng Xiao   +3 more
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Anti-Ramsey numbers for three classes of special subgraphs in wheel graph(轮图中三类特殊子图的anti-Ramsey数)

Zhejiang Daxue xuebao. Lixue ban
A subgraph in an edge-colored graph is called rainbow, if all its edges have different colors. Given two graphs G and H, the anti-Ramsey number for H in G, denoted by ar(G,H), is the maximum number of colors in an edge-coloring of G such that G contains ...
覃忠美(QIN Zhongmei), 申悦(SHEN Yue), 刘奋进(LIU Fenjin)   +2 more
doaj   +1 more source