A Characterization of 2-Tree Proper Interval 3-Graphs

<table>An infinite family of forbidden induced subgraphs for proper interval <svg height="13.3" id="M100" style="vertical-align:-3.50804pt" version="1.1" viewbox="0 0 10.2 13.3" width="10.2" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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Journal of Discrete Mathematics

A Characterization of 2-Tree Proper Interval 3-Graphs

Figure 3