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arXiv · 2111.00148

On Small-Depth Tree Augmentations

Ojas Parekh·R. Ravi·Michael Zlatin
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Abstract

We study the Weighted Tree Augmentation Problem for general link costs. We show that the integrality gap of the ODD-LP relaxation for the (weighted) Tree Augmentation Problem for a $k$-level tree instance is at most $2 - \frac{1}{2^{k-1}}$. For 2- and 3-level trees, these ratios are $\frac32$ and $\frac74$ respectively. Our proofs are constructive and yield polynomial-time approximation algorithms with matching guarantees.

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Ojas Parekh, R. Ravi, Michael Zlatin. 2021-10-30. On Small-Depth Tree Augmentations. https://arxiv.org/abs/2111.00148

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