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arXiv · 1402.5904

On the Integrality Ratio of the Subtour LP for Euclidean TSP

Stefan Hougardy
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Abstract

A long standing conjecture says that the integrality ratio of the subtour LP for metric TSP is $4/3$. A well known family of graphic TSP instances achieves this lower bound asymptotically. For Euclidean TSP the best known lower bound on the integrality ratio was $8/7$. We improve this value by presenting a family of Euclidean TSP instances for which the integrality ratio of the subtour LP converges to 4/3.

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Stefan Hougardy. 2014-02-24. On the Integrality Ratio of the Subtour LP for Euclidean TSP. https://arxiv.org/abs/1402.5904

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