Finding k-edge-outerplanar graph embeddings

OPG_k_edge_outerplanar_embedding_polynomial

Medium ★★ Graph Theory

Status solved high confidence

Yu proves that the minimum edge-outerplanarity of a planar graph can be computed in polynomial time, answering Bentz's question affirmatively.

Cited literature (1)

Reviewer notes. These status corrections report results attributed to existing papers or to the final source version. Graph-Theory-LLM-Proofs located and checked the implication; it is not credited as the author of the result.

Auto-reviewed 2026-09-16 with gpt-6-astra.

Conjecture. It has been shown that a $ k $ -outerplanar embedding for which $ k $ is minimal can be found in polynomial time. Does a similar result hold for $ k $ -edge-outerplanar graphs?
Keywords: planar graph · polynomial algorithm

Discussion

A $ k $ -outerplanar graph [Baker] with $ k > 0 $ is a planar graph having an embedding with at most $ k $ layers of vertices such that after removing iteratively the vertices (and their adjacent edges) lying on the outer face $ k $ times, we obtain the empty graph. A $ k $ -edge-outerplanar graph [Bentz] is defined to be a planar graph having an embedding with at most $ k $ layers of edges such that after removing iteratively the edges lying on the outer face $ k $ times, we obtain a graph with no edge. All $ k $ -edge-outerplanar graphs are $ k $ -outerplanar graphs. Given a planar graph, Bienstock and Monma have shown that a $ k $ -outerplanar embedding for which $ k $ is minimal can be found in polynomial time. Does a similar result hold for $ k $ -edge-outerplanar graphs?

Bibliography

  • [?] C. Bentz, “Disjoint paths in sparse graphs,” Discrete Appl. Math., vol. 157, no. 17, pp. 3558–3568, 2009
  • [?] D. Bienstock and C. L. Monma, “On the complexity of embedding planar graphs to minimize certain distance measures,” Algorithmica, vol. 5, no. 1–4, pp. 93–109, 1990
  • [?] B. S. Baker, “Approximation algorithms for np-complete problems on planar graphs,” J. ACM, vol. 41, no. 1, pp. 153–180, 1994