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arXiv · 2605.26859

Mixed Unit Interval Bigraphs : A Characterization

Ashok Kumar Das·Rajkamal Sahu·Amina Khatun
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Abstract

The class of intersection bigraphs of unit intervals of the real line whose ends may be open or closed is called a class of mixed unit interval bigraphs. This class of bigraphs is a strict superclass of the class of unit interval bigraphs. In a previous paper [6] we have provided four infinite families of forbidden induced subgraphs including two separate forbidden induced subgraphs of mixed unit interval bigraphs. In that paper, we also posed a conjecture concerning characterization of mixed unit interval bigraphs and verified parts of it. In the present paper we shall give a complete characterization of mixed unit interval bigraphs.

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Ashok Kumar Das, Rajkamal Sahu, Amina Khatun. 2026-05-26. Mixed Unit Interval Bigraphs : A Characterization. https://arxiv.org/abs/2605.26859

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