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arXiv · 1505.06811

An Improved Combinatorial Algorithm for Boolean Matrix Multiplication

Huacheng Yu
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Abstract

We present a new combinatorial algorithm for triangle finding and Boolean matrix multiplication that runs in $\hat{O}(n^3/\log^4 n)$ time, where the $\hat{O}$ notation suppresses poly(loglog) factors. This improves the previous best combinatorial algorithm by Chan that runs in $\hat{O}(n^3/\log^3 n)$ time. Our algorithm generalizes the divide-and-conquer strategy of Chan's algorithm. Moreover, we propose a general framework for detecting triangles in graphs and computing Boolean matrix multiplication. Roughly speaking, if we can find the "easy parts" of a given instance efficiently, we can solve the whole problem faster than $n^3$.

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Huacheng Yu. 2015-05-26. An Improved Combinatorial Algorithm for Boolean Matrix Multiplication. https://arxiv.org/abs/1505.06811

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