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Vertex-degree function index on tournaments | ||
Communications in Combinatorics and Optimization | ||
مقاله 12، دوره 10، شماره 2، شهریور 2025، صفحه 443-452 اصل مقاله (433.07 K) | ||
نوع مقاله: Original paper | ||
شناسه دیجیتال (DOI): 10.22049/cco.2023.28904.1771 | ||
نویسندگان | ||
Sergio Bermudo1؛ Roberto Cruz2؛ Juan Rada* 2 | ||
1Department of Economy, Quantitative Methods and Economic History, Pablo de Olavide University, Carretera de Utrera Km. 1, 41013-Sevilla, Spain | ||
2Instituto de Matemáticas, Universidad de Antioquia, Medellín, Colombia | ||
چکیده | ||
Let $G$ be a simple graph with vertex set $V=V(G)$ and edge set $E=E(G)$. For a real function $f$ defined on nonnegative real numbers, the vertex-degree function index $H_{f}(G)$ is defined as $$H_{f}(G)=\sum_{u\in V(G)}f(d_{u}).$$ In this paper we introduce the vertex-degree function index $H_{f}(D)$ of a digraph $D$. After giving some examples and basic properties of $H_{f}(D)$, we find the extremal values of $H_{f}$ among all tournaments with a fixed number of vertices, when $f$ is a continuous and convex (or concave) real function on $\left[ 0,+\infty \right)$. | ||
کلیدواژهها | ||
Tournaments؛ Vertex-degree function index؛ Vertex-degree-based topological index | ||
مراجع | ||
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