lil correction: two subgroups having trivial intersection is not enough for the order of the union to be the product of orders... you also need conjugation by an element of one to be closed in the oth...
@nprofile1q... as a non-mathematician seeing this across my timeline every so often really feels like there's a sorceress walking past you mumbling about some cursed artifact you've never heard of and I think that's amazing
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