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Martin R
Martin R
9:36 AM
@ArcticChar There is one "Yves Daoust" account who joined Stack Overflow (and some other sites) many years ago. Two of his questions on SO were migrated to Math.SE in 2017. Only ten days ago he joined Math.SE. That explains why a new account has questions from 2017 in their profile.
There used to be another "Yves Daoust" on Math.SE (with more than 100K reputation, if I remember correctly), but that account does not exist anymore. We mere mortals cannot know what happened (and the moderators won't tell us), but it is not necessary because of fraudulent activity.
^ s/necessary/necessarily/
 
 
1 hour later…
Martin Sleziak
Martin Sleziak
10:43 AM
The same user was mentioned a bit ago in this room: chat.stackexchange.com/transcript/19138/2021/8/16
in Martin Sleziak's room, Aug 16 at 11:01, by Martin Sleziak
It seems that this user deleted the Mathematics account at some point after May 2021. You're right that he still has a StackOverflow account.
 

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