Results 31 to 40 of about 999 (266)
Extremal Permanents of Laplacian Matrices of Unicyclic Graphs
The extremal problem of Laplacian permanents of graphs is a classical and challenging topic in algebraic combinatorics, where the inherent #P-complete complexity of permanent computation renders this pursuit particularly intractable.
Tingzeng Wu +2 more
doaj +1 more source
Spectral radius and extremal graphs for class of unicyclic graph with pendant vertices
In this article, we research on the spectral radius of extremal graphs for the unicyclic graphs with girth g mainly by the graft transformation and matching and obtain the upper bounds of the spectral radius of unicyclic graphs.
Lu Zhi +5 more
doaj +1 more source
An advance in infinite graph models for the analysis of transportation networks
This paper extends to infinite graphs the most general extremal issues, which are problems of determining the maximum number of edges of a graph not containing a given subgraph.
Cera Martín, Fedriani Eugenio M.
doaj +1 more source
Extremal traceable graphs with non-traceable edges [PDF]
By \(\text{NT}(n)\) we denote the set of graphs of order \(n\) which are traceable but have non-traceable edges, i.e. edges which are not contained in any hamiltonian path.
Adam Paweł Wojda
doaj +1 more source
Design and analysis strategies for robust microbiome ageing research
The gut microbiome changes with age and associates with age‐related morbidity and mortality, establishing it as a potential biomarker and intervention target for ageing. Realising this potential requires methodological rigour, yet distinguishing biological signals from methodological artefacts remains challenging across cohorts. This review provides an
Mark Olenik +5 more
wiley +1 more source
Degree-based topological indices play a central role in characterizing graph structures and their chemical applications. Among these, multiplicative Zagreb indices have attracted considerable attention due to their strong discriminative power and ...
Mahdieh Azari +2 more
doaj +1 more source
Single‐cell DNA methylation (scDNAme) profiling maps epimutational clonal evolution, revealing mechanisms of malignancy and therapeutic resistance across diverse cancer types. By providing a high‐resolution landscape of intratumoral heterogeneity, these technologies empower precise patient stratification, guide the development of enhanced ...
Ik Soo Kim
wiley +1 more source
Extremal graphs for alpha-index
Let N(G) be the number of vertices of the graph G. Let Pl(Bi) be the tree obtained of the path Pl and the trees B1,B2, ...,Bl by identifying the root vertex of Bi with the i-th vertex of Pl. Let Vmn = {Pl(Bi) : N(Pl(Bi)) =n; N(Bi) ≥ 2; l ≥ m}.
Eber Lenes +3 more
doaj
Third Smallest Wiener Polarity Index of Unicyclic Graphs
The Wiener polarity index WP(G) of a graph G is the number of unordered pairs of vertices {u,v} where the distance between u and v is 3. In this paper, we determine the third smallest Wiener polarity index of unicyclic graphs. Moreover, the corresponding
Wei Fang +5 more
doaj +1 more source
Exact Formulae for Degree Distance Indices of Sum Graphs
The degree distance index (DDI) is a vertex-degree weighted version of a well-known index that is called by Wiener index (WI). In extremal theory of graphs, improving the bounds with best possible values is a worth investigating problem.
Muhammad Javaid +3 more
doaj +1 more source

