Results 91 to 100 of about 46,626 (239)

Graphs with 3-Rainbow Index n − 1 and n − 2

Discussiones Mathematicae Graph Theory, 2015
Let G = (V (G),E(G)) be a nontrivial connected graph of order n with an edge-coloring c : E(G) → {1, 2, . . . , q}, q ∈ N, where adjacent edges may be colored the same. A tree T in G is a rainbow tree if no two edges of T receive the same color.
Li Xueliang, Schiermeyer Ingo, Yang Kang, Zhao Yan   +3 more
doaj   +1 more source

The generalized 3-connectivity of Lexicographic product graphs [PDF]

Discrete Mathematics & Theoretical Computer Science, 2014
Graph ...
Xueliang Li, Yaping Mao
doaj   +1 more source

Random Walks in the Quarter Plane: Algebraic Methods, Boundary Value Problems, Applications to Queueing Systems and Analytic Combinatorics

, 2018
This monograph aims to promote original mathematical methods to determine the invariant measure of two-dimensional random walks in domains with boundaries.
G. Fayolle, R. Iasnogorodski, V. Malyshev   +2 more
semanticscholar   +1 more source

On Fork‐Free t‐Perfect Graphs

Journal of Graph Theory, EarlyView.
ABSTRACT In an effort to understand the complexity of the maximum independent set problem, Chvátal introduced t‐perfect graphs. While a full characterization of this class remains open, important progress has been made for claw‐free graphs [Bruhn and Stein, Math. Program. 2012] and P 5 ${P}_{5}$‐free graphs [Bruhn and Fuchs, SIAM J. Discrete Math. 2017]
Yixin Cao, Shenghua Wang
wiley   +1 more source

Combinatorics

, 2006
This is the report on the Oberwolfach workshop on Combinatorics, held 1–7 January 2006. Combinatorics is a branch of mathematics studying families of mainly, but not exclusively, finite or countable structures – discrete objects.
Hans Jürgen Prömel, László Lovász
core   +3 more sources

Extremal skew energy of digraphs with no even cycles [PDF]

Transactions on Combinatorics, 2014
Let $D$ be a digraph with skew-adjacency matrix $S(D)$. Then the skew energy of $D$ is defined to be the sum of the norms of all eigenvalues of $S(D)$. Denote by $mathcal{O}_n$ the class of digraphs on order $n$ with no even cycles, and by $mathcal{O ...
Jing Li, Xueliang Li, Huishu Lian
doaj  

Statistics of Feynman amplitudes in ϕ 4-theory

Journal of High Energy Physics, 2023
The amplitude of subdivergence-free logarithmically divergent Feynman graphs in ϕ 4-theory in 4 spacetime dimensions is given by a single number, the Feynman period. We numerically compute the periods of 1.3 million completed graphs, this represents more
Paul-Hermann Balduf
doaj   +1 more source

Combinatorics of JENGA. [PDF]

Australas. J Comb., 2020
JENGA, a very popular game of physical skill, when played by perfect players, can be seen as a pure combinatorial ruleset. Taking that into account, it is possible to play with more than one tower; a move is made by choosing one of the towers, removing a block from there, that is, a disjunctive sum.
Carvalho, Alda, Neto, João, Santos, Carlos   +2 more
openaire   +1 more source

Tree Independence Number III. Thetas, Prisms and Stars

Journal of Graph Theory, EarlyView.
ABSTRACT We prove that for every t ∈ N $t\in {\mathbb{N}}$ there exists τ = τ ( t ) ∈ N $\tau =\tau (t)\in {\mathbb{N}}$ such that every (theta, prism, K 1 , t ${K}_{1,t}$)‐free graph has tree independence number at most τ $\tau $ (where we allow “prisms” to have one path of length zero).
Maria Chudnovsky, Sepehr Hajebi, Nicolas Trotignon   +2 more
wiley   +1 more source

Teaching of probability theory and combinatorics at secondary schools

Lietuvos Matematikos Rinkinys, 2004
The topics of probability theory and combinatorics were brought into curricula of Lithuanian secondary schools ten years ago. The problems of teaching and actual situation of apprehension of concepts of prob­ability theory and combinatorics are analyzed.
Eugenijus Stankus
doaj   +3 more sources