Results 41 to 50 of about 96,628 (243)
Discrete Mathematics, 2000 The authors study coverings of non-bipartite graphs by bipartite graphs. In particular, they enumerate regular bipartite coverings for orders which are twice a prime.
Archdeacon, D +3 more
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Bipartite embedding of (p,q)-trees [PDF]
Opuscula Mathematica, 2006 A bipartite graph \(G=(L,R;E)\) where \(V(G)=L\cup R\), \(|L|=p\), \(|R| =q\) is called a \((p,q)\)-tree if \(|E(G)|=p+q-1\) and \(G\) has no cycles. A bipartite graph \(G=(L,R;E)\) is a subgraph of a bipartite graph \(H=(L',R';E')\) if \(L\subseteq L'\)
Beata Orchel
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The Median Problem on k-Partite Graphs
Discussiones Mathematicae Graph Theory, 2015 In a connected graph G, the status of a vertex is the sum of the distances of that vertex to each of the other vertices in G. The subgraph induced by the vertices of minimum (maximum) status in G is called the median (anti-median) of G.
Pravas Karuvachery, Vijayakumar Ambat
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Homomorphisms of binary Cayley graphs
, 2015 A binary Cayley graph is a Cayley graph based on a binary group. In 1982, Payan proved that any non-bipartite binary Cayley graph must contain a generalized Mycielski graph of an odd-cycle, implying that such a graph cannot have chromatic number 3.
Beaudou, Laurent +2 more
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Discrete Applied Mathematics, 1984 The isoperimetric constant \(i(G)\) of a cubic graph \(G\) is \(i(G)=\min | \partial U| /| U|\) where \(|\cdot|\) is cardinality, \(U\) runs over all subsets of the vertex set \(VG\) satisfying \(| U| \leq \frac12 | VG|\), and \(| \partial U|\) is the number of edges running from \(U\) to the complement \(VG\backslash U\).
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A Note on the Permanental Roots of Bipartite Graphs
Discussiones Mathematicae Graph Theory, 2014 It is well-known that any graph has all real eigenvalues and a graph is bipartite if and only if its spectrum is symmetric with respect to the origin.
Zhang Heping, Liu Shunyi, Li Wei
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Discrete Applied Mathematics, 1987 It is shown that bipartite permutation graphs have good algorithmic properties in contrast to general bipartite or permutation graphs. Two characterizations of these graphs are presented which lead to a linear time recognition algorithm and also to polynomial algorithms for Hamiltonian problems, a variant of the crossing number problem and the minimum ...
BrandstรคdtAndreas +2 more
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On the cubicity of bipartite graphs [PDF]
Information Processing Letters, 2009 {\it A unit cube in $k$-dimension (or a $k$-cube) is defined as the cartesian product $R_1 \times R_2 \times ... \times R_k$, where each $R_i$ is a closed interval on the real line of the form $[a_i, a_i+1]$. The {\it cubicity} of $G$, denoted as $cub(G)$, is the minimum $k$ such that $G$ is the intersection graph of a collection of $k$-cubes.
Chandran, Sunil L +2 more
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Electronic Notes in Discrete Mathematics, 1999 Two graphs \(G\) and \(H\) on the vertex set \(V\) are \(P_4\)-isomorphic if there is a permutation \(\pi\) on \(V\) such that, for all subsets \(S\) of \(V\), \(S\) induces a chordless \(P_4\) in \(G\) if and only if \(\pi (S)\) induces a \(P_4\) in \(H\). The author characterizes all graphs \(P_4\)-isomorphic to a bipartite graph. For example, we can
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Bipartite Diametrical Graphs of Diameter 4 and Extreme Orders
International Journal of Mathematics and Mathematical Sciences, 2008 We provide a process to extend any bipartite diametrical graph of diameter 4 to an ๐-graph of the same diameter and partite sets. For a bipartite diametrical graph of diameter 4 and partite sets ๐ and ๐, where 2๐=|๐|โค|๐|, we prove that 2๐ is a sharp ...
Salah Al-Addasi, Hasan Al-Ezeh
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