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arXiv · 2405.03018

TSP Escapes the $O(2^n n^2)$ Curse

Mihail Stoian
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Abstract

The dynamic programming solution to the traveling salesman problem due to Bellman, and independently Held and Karp, runs in time $O(2^n n^2)$, with no improvement in the last sixty years. We break this barrier for the first time by designing an algorithm that runs in deterministic time $2^n n^2 / 2^{\Omega(\sqrt{\log n})}$. We achieve this by strategically remodeling the dynamic programming recursion as a min-plus matrix product, for which faster-than-na\"ive algorithms exist.

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Mihail Stoian. 2024-05-05. TSP Escapes the $O(2^n n^2)$ Curse. https://arxiv.org/abs/2405.03018

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