On Chemical Trees That Maximize Atom–Bond Connectivity Index, Its Exponential Version, and Minimize Exponential Geometric–Arithmetic Index

A chemical tree is a tree that has no vertex of degree greater than 4. We denote the set of chemical trees with n vertices as Cn. The ABC index of a chemical tree T is defined as ABC (T) = X 1≤i≤j≤4 mi,j (T) s i + j − 2 ij , where mi,j (T) is the number of edges in T joining vertices of degree i and...

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Autores:
Rada Rincón, Juan Pablo
Cruz Rodes, Roberto
Monsalve Aristizabal, Juan Daniel
Tipo de recurso:
Article of investigation
Fecha de publicación:
2020
Institución:
Universidad de Antioquia
Repositorio:
Repositorio UdeA
Idioma:
eng
OAI Identifier:
oai:bibliotecadigital.udea.edu.co:10495/46414
Acceso en línea:
https://hdl.handle.net/10495/46414
Palabra clave:
Árboles (Teoría de grafos)
Trees (Graph theory)
Álgebra
Algebra
Teoría de conjuntos
Set theory
Rights
openAccess
License
http://creativecommons.org/licenses/by-nc-sa/4.0/
Description
Summary:A chemical tree is a tree that has no vertex of degree greater than 4. We denote the set of chemical trees with n vertices as Cn. The ABC index of a chemical tree T is defined as ABC (T) = X 1≤i≤j≤4 mi,j (T) s i + j − 2 ij , where mi,j (T) is the number of edges in T joining vertices of degree i and j. Furtula, Graovac and Vukiˇcevi´c in 2009 found trees with maximal ABC index among all trees in Cn, when n ≡ 1 mod 4. In this paper we find the trees with maximal ABC index in Cn for all n. Using the same technique, we find the trees with maximal eABC and minimal e GA over Cn for all n, where eABC (T) = X 1≤i≤j≤4 mi,j (T) e qi+j−2 ij and e GA (T) = X 1≤i≤j≤4 mi,j (T) e 2 √ij i+j .