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Paper

TESTING March 17, 2026

A characterization of terminal planar networks by forbidden structures

Authors

Haruki Miyaji, Yuki Noguchi, Hexuan Liu, Takatora Suzuki, Keita Watanabe, Taoyang Wu, Momoko Hayamizu

Abstract

The class of terminal planar networks was recently introduced from a biological perspective in relation to the visualization of phylogenetic networks, and its connection to upward planar networks has been established. We provide a Kuratowski-type theorem that characterizes terminal planar networks by a finite set of forbidden structures, defined via six families of 0/1-labeled graphs. Another characterization based on planarity of supergraphs yields linear-time algorithms for testing terminal planarity and for computing such planar drawings. We describe an application that is potentially relevant in broader, non-phylogenetic settings. We also discuss a connection of our main result to an open problem on the forbidden structures of single-source upward planar networks.

Metadata

arXiv ID: 2603.16657
Provider: ARXIV
Primary Category: math.CO
Published: 2026-03-17
Fetched: 2026-03-18 06:02

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