Skew braces of squarefree order. (English) Zbl 1476.16034

The authors use the theory of Hopf-Galois extensions and, in particular, the number of non-isomorphic Hopf-Galois extensions of square-free degree to enumerate skew braces of square-free order. As an application, a conjecture on the number of isomorphism classes of skew braces of order \(2pq\) for distinct odd primes \(p\) and \(q\) is confirmed.


16T25 Yang-Baxter equations
16Y99 Generalizations
12F10 Separable extensions, Galois theory
Full Text: DOI arXiv


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