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arXiv · 2512.01175

Structural and Spectral Properties of Strictly Interval Graphs

Claudia Justel·Lilian Markenzon
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Abstract

In this paper we deal with a subclass of chordal graphs, which are simultaneously strictly chordal and interval, the strictly interval graphs. We present a new characterization of the class that leads to a simple linear recognition algorithm. Next we introduce a new subclass of strictly interval graphs, the $SI$-core graphs, that are non-split and non-cograph graphs and show that several elements of the new class are Laplacian integral

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Claudia Justel, Lilian Markenzon. 2025-12-01. Structural and Spectral Properties of Strictly Interval Graphs. https://arxiv.org/abs/2512.01175

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