Results 41 to 50 of about 145,190 (272)
Skew Randi'c matrix and skew Randi'c energy [PDF]
Let $G$ be a simple graph with an orientation $sigma$, which assigns to each edge a direction so that $G^sigma$ becomes a directed graph. $G$ is said to be the underlying graph of the directed graph $G^sigma$.
Ran Gu, Fei Huang, Xueliang Li
doaj
Rainbow Vertex-Connection and Forbidden Subgraphs
A path in a vertex-colored graph is called vertex-rainbow if its internal vertices have pairwise distinct colors. A vertex-colored graph G is rainbow vertex-connected if for any two distinct vertices of G, there is a vertex-rainbow path connecting them ...
Li Wenjing, Li Xueliang, Zhang Jingshu
doaj +1 more source
On interval number in cycle convexity [PDF]
Recently, Araujo et al. [Manuscript in preparation, 2017] introduced the notion of Cycle Convexity of graphs. In their seminal work, they studied the graph convexity parameter called hull number for this new graph convexity they proposed, and they ...
Julio Araujo+3 more
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Erdős-Gallai-Type Results for Total Monochromatic Connection of Graphs
A graph is said to be total-colored if all the edges and the vertices of the graph are colored. A total-coloring of a graph is a total monochromatically-connecting coloring (TMC-coloring, for short) if any two vertices of the graph are connected by a ...
Jiang Hui, Li Xueliang, Zhang Yingying
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General Randic matrix and general Randi'c energy [PDF]
Let $G$ be a simple graph with vertex set $V(G) = {v_1, v_2,ldots , v_n}$ and $d_i$ the degree of its vertex $v_i$, $i = 1, 2, cdots, n$. Inspired by the Randi'c matrix and the general Randi'c index of a graph, we introduce the concept of general ...
Ran Gu;, Fei Huang, Xueliang Li
doaj
The 3-Rainbow Index of a Graph
Let G be a nontrivial connected graph 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.
Chen Lily+3 more
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Open questions about Ramsey-type statements in reverse mathematics [PDF]
Ramsey's theorem states that for any coloring of the n-element subsets of N with finitely many colors, there is an infinite set H such that all n-element subsets of H have the same color.
Patey, Ludovic
core +3 more sources
Constructing elliptic curve isogenies in quantum subexponential time
Given two ordinary elliptic curves over a finite field having the same cardinality and endomorphism ring, it is known that the curves admit a nonzero isogeny between them, but finding such an isogeny is believed to be computationally difficult.
Childs Andrew+2 more
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On the Rainbow Vertex-Connection
A vertex-colored graph is rainbow vertex-connected if any two vertices are connected by a path whose internal vertices have distinct colors. The rainbow vertex-connection of a connected graph G, denoted by rvc(G), is the smallest number of colors that ...
Li Xueliang, Shi Yongtang
doaj +1 more source
Backbone colouring and algorithms for TDMA scheduling [PDF]
We investigate graph colouring models for the purpose of optimizing TDMA link scheduling in Wireless Networks. Inspired by the BPRN-colouring model recently introduced by Rocha and Sasaki, we introduce a new colouring model, namely the BMRN-colouring ...
Julien Bensmail+4 more
doaj +1 more source