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arXiv · 2504.01158

On the Number of Disconnected Character Degree Graphs Satisfying P\'alfy's Inequality

Mark L. Lewis·Andrew Summers
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Abstract

Let $G$ be a finite solvable group with disconnected character degree graph $\Delta(G)$. Under these conditions, it follows from a result of P\'alfy that $\Delta(G)$ consists of two connected components. Another result of P\'alfy's gives an inequality relating the sizes of these two connected components. In this paper, we calculate the number of possible component size pairs that satisfy P\'alfy's inequality. Additionally, for a fixed positive integer $n$, the number of distinct graph orders for which exactly $n$ component size pairs satisfy P\'alfy's inequality is shown.

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Mark L. Lewis, Andrew Summers. 2025-04-01. On the Number of Disconnected Character Degree Graphs Satisfying P\'alfy's Inequality. https://arxiv.org/abs/2504.01158

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