论文信息 - Product-free sets in the free semigroup

Product-free sets in the free semigroup

In this paper, we study product-free subsets of the free semigroup over a finite alphabet $A$. We prove that the maximum density of a product-free subset of the free semigroup over $A$, with respect to the natural measure that assigns a weight of $|A|^{-n}$ to each word of length $n$, is precisely $1/2$.

Imre Leader | Shoham Letzter | Mark Walters | Bhargav Narayanan

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