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arXiv · 2512.23209

Extremal $ABS$ Spectral Radius in Bicyclic and Bipartite Unicyclic Graphs

Swathi Shetty·B. R. Rakshith·Sayinath Udupa N. V
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Abstract

The ABS spectral radius of a graph G is defined as the largest eigenvalue of its $ABS$ matrix. Motivated by recent studies on this parameter, in this paper, we determine the bipartite unicyclic graphs that attain the largest $ABS$ spectral radius. Furthermore, we characterize the bicyclic graphs that attain the largest and the second largest $ABS$ spectral radii.

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Swathi Shetty, B. R. Rakshith, Sayinath Udupa N. V. 2025-12-29. Extremal $ABS$ Spectral Radius in Bicyclic and Bipartite Unicyclic Graphs. https://arxiv.org/abs/2512.23209

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