Extremal graphs for alpha-index

• Lenes, Eber ^[1] ; García, Henry ^[1] ; Figueroa, Ariel ^[1] ; Mercado, Fabian ^[1]
  1. [1] Universidad del Sinú

     Universidad del Sinú

     Colombia

     
• Localización: Integración: Temas de matemáticas, ISSN 0120-419X, Vol. 38, Nº. 1, 2020, págs. 15-31
• Idioma: inglés
• DOI: 10.18273/revint.v38n1-202002
• Títulos paralelos:
  • Grafos extremales para alfa-índice
• Enlaces
  • Texto completo (pdf)
• Resumen
  • español

    Sea N(G) el número de vértices del grafo G. Sean Pl(Bi) los árboles obtenidos del camino Pl y los árboles B1,B2, ...,Bl, identificando el vértice raíz de Bi con el i-th vértice dePl. Sea Vmn = {Pl(Bi) : N(Pl(Bi)) =n; N(Bi) ≥ 2; l ≥ m}. En este artículo determinamos el árbol que tiene el \alpha-índice más grande entre todos los árboles en Vmn.

  • English

    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}. In this paper, we determine the tree that has the largest \alpha-index among all the trees in Vmn.

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