Correction to: Nature https://doi.org/10.1038/s41586-020-2445-zPublished online 15 July 2020

In this Article, owing to an error during the production process, the citation to Fig. 4d in the sentence beginning ‘In these samples, the number of toroids…’ erroneously read ‘Fig A Star of David catenane. 4d’. The original Article has been corrected online.