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arXiv · 2605.22160

Minimum second neighborhood degree energy of commuting graphs of finite rings

Payal Tak·Jutirekha Dutta·Rajat Kanti Nath
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Abstract

In this paper, we compute minimum second neighborhood degree spectrum and energy of commuting graphs of certain finite non-commutative rings. In particular, we consider non-commutative rings of order $p^2, p^3, p^4, p^5, p^2q$ and $p^3q$, where $p$ and $q$ are primes. We shall also show that the commuting graphs of these rings are MSN-integral but not MSN-hyperintegral. Finally, employing the techniques used in this paper, we prove Conjecture 3 of [Nath, R. K., Fasfous, W. N. T., Das, K. C. and Shang, Y. Common neighbourhood energy of commuting graphs of finite groups, {\em Symmetry} {\bf 13}(9), Article No. 1651, 2021.] and Conjecture 3.12 of [W. N. T. Fasfous and Nath, R. K. Common neighborhood spectrum and energy of commuting graphs of finite rings, \emph{ Palestine J. Math.} \textbf{13}(1), 66--76, 2024.]. We conclude this paper with two open problems.

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Payal Tak, Jutirekha Dutta, Rajat Kanti Nath. 2026-05-21. Minimum second neighborhood degree energy of commuting graphs of finite rings. https://arxiv.org/abs/2605.22160

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