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Related papers: Balanced Spanning Caterpillars

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A bipartite graph $G=(A, B, E)$ is said to be a biconvex bipartite graph if there exist orderings $<_A$ in $A$ and $<_B$ in $B$ such that the neighbors of every vertex in $A$ are consecutive with respect to $<_B$ and the neighbors of every…

Combinatorics · Mathematics 2024-06-04 Dhanyamol Antony , Anita Das , Shirish Gosavi , Dalu Jacob , Shashanka Kulamarva

Let $T$ be a tree, a vertex of degree one and a vertex of degree at least three is called a leaf and a branch vertex, respectively. The set of leaves of $T$ is denoted by $Leaf(T)$. The subtree $T-Leaf(T)$ of $T$ is called the stem of $T$…

Combinatorics · Mathematics 2018-02-28 Pham Hoang Ha

A spanning generalized caterpillar is a spanning tree in which all vertices of degree more than two are on a path. In this note, we find a relation between the existence of spanning generalized caterpillar and the independence and…

Combinatorics · Mathematics 2013-02-21 M. Pedramfar , M. Shokrian , M. Tefagh

A semiregular tree is a tree where all non-pendant vertices have the same degree. Belardo et al. (MATCH Commun. Math. Chem. 61(2), pp. 503-515, 2009) have shown that among all semiregular trees with a fixed order and degree, a graph with…

Combinatorics · Mathematics 2009-06-09 Tuerker Biyikoglu , Josef Leydold

A graph $G$ is said to be Hamiltonian if it contains a spanning cycle. In this work, we investigate the Hamiltonian completeness of certain classes of caterpillar graphs, which are trees with a central path to which all other vertices are…

A long-standing conjecture on spanning trees of a hypercube states that a balanced tree on $2^n$ vertices with maximum degree at most $3$ spans the hypercube of dimension $n$ \cite{havel1986}. In this paper, we settle the conjecture for a…

Combinatorics · Mathematics 2021-10-13 Rishikant Rajdeepak , V. Sunitha

For a connected graph $G:=(V,E)$, the Steiner distance $d_G(X)$ among a set of vertices $X$ is the minimum size among all the connected subgraphs of $G$ whose vertex set contains $X$. The $k-$Steiner distance matrix $D_k(G)$ of $G$ is a…

Combinatorics · Mathematics 2021-08-31 Ali Azimi , R. B. Bapat , Shivani Goel

A caterpillar tree is a connected, acyclic, graph in which all vertices are either a member of a central path, or joined to that central path by a single edge. In other words, caterpillar trees are the class of trees which become path…

Combinatorics · Mathematics 2018-10-30 Jacob Crabtree

The characteristic polynomials of the adjacency matrix of line graphs of caterpillars and then the characteristic polynomials of their Laplacian or signless Laplacian matrices are characterized, using recursive formulas. Furthermore, the…

Combinatorics · Mathematics 2013-06-20 D. M. Cardoso , M. A. A. de Freitas , E. A. Martins , M. Robbinao , B. San Martín

We consider certain matrix-products where successive matrices in the product belong alternately to a particular qualitative class or its transpose. The main theorems relate structural and spectral properties of these matrix-products to the…

Combinatorics · Mathematics 2015-02-25 Murad Banaji , Carrie Rutherford

Let $T$ be a tree such that all its vertices of degree more than two lie on one path, that is, $T$ is a caterpillar subdivision. We prove that there exists $\epsilon>0$ such that for every graph $G$ with $|V(G)|\ge 2$ not containing $T$ as…

Combinatorics · Mathematics 2018-10-02 Anita Liebenau , Marcin Pilipczuk , Paul Seymour , Sophie Spirkl

A $k$-tree is a spanning tree in which every vertex has degree at most $k$. In this paper, we provide a sufficient condition for the existence of a $k$-tree in a connected graph with fixed order in terms of the adjacency spectral radius and…

Combinatorics · Mathematics 2023-04-24 Dandan Fan , Sergey Goryainov , Xueyi Huang , Huiqiu Lin

The edge-bandwidth of a graph is the minimum, over all labelings of the edges with distinct integers, of the maximum difference between labels of two incident edges. We prove that edge-bandwidth is at least as large as bandwidth for every…

Combinatorics · Mathematics 2007-05-23 Tao Jiang , Dhruv Mubayi , Aditya Shastri , Douglas B. West

The energy $En(G)$ of a graph $G$ is defined as the sum of the absolute values of its eigenvalues. The Hosoya index $Z(G)$ of a graph $G$ is the number of independent edge subsets of $G$, including the empty set. For any given degree…

Combinatorics · Mathematics 2024-10-23 Eric O. D. , Andriantiana , Xhanti Sinoxolo

A branch vertex in a tree is a vertex of degree at least three. We prove that, for all $s\geq 1$, every connected graph on $n$ vertices with minimum degree at least $(\frac{1}{s+3}+o(1))n$ contains a spanning tree having at most $s$ branch…

Combinatorics · Mathematics 2019-10-10 Louis DeBiasio , Allan Lo

The $\textit{$m$-deck}$ of an $n$-vertex graph is the multiset of unlabeled induced subgraphs with $m$ vertices. Caterpillars are trees in which all nonleaf vertices lie on a single path. We prove for $n\ge48$ that any $n$-vertex…

Combinatorics · Mathematics 2025-12-01 Alexandr V. Kostochka , Zishen Qu , Maddy Ritter , Douglas B. West

We investigate the structure of trees that have minimal algebraic connectivity among all trees with a given degree sequence. We show that such trees are caterpillars and that the vertex degrees are non-decreasing on every path on…

Combinatorics · Mathematics 2008-10-07 Tuerker Biyikoglu , Josef Leydold

This paper studies a \emph{packing} problem in the so-called beyond-planar setting, that is when the host graph is ``almost-planar'' in some sense. Precisely, we consider the case that the host graph is $k$-planar, i.e., it admits an…

Combinatorics · Mathematics 2023-01-04 Carla Binucci , Emilio Di Giacomo , Michael Kaufmann , Giuseppe Liotta , Alessandra Tappini

The celebrated Erd\H{o}s-Hajnal conjecture states that for every proper hereditary graph class $\mathcal{G}$ there exists a constant $\varepsilon = \varepsilon(\mathcal{G}) > 0$ such that every graph $G \in \mathcal{G}$ contains a clique or…

Combinatorics · Mathematics 2017-10-25 Anita Liebenau , Marcin Pilipczuk

A graph is called set-sequential if its vertices can be labeled with distinct nonzero vectors in $\mathbb{F}_2^n$ such that when each edge is labeled with the sum$\pmod{2}$ of its vertices, every nonzero vector in $\mathbb{F}_2^n$ is the…

Combinatorics · Mathematics 2017-10-17 Louis Golowich , Chiheon Kim
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