Some clarifications what I meant and know: First, it is not clear if moderators deleted it it was the community user, this would also be like this if it happened via sufficiently many flags; however from the timeline in particular for the last I would rather guess it was in the end one powerful moderator flag, it had one flag a long time today and then was gone (this could however also be a coincindence).

Second, I flagged the question twice for attention, after the first repost, and now after the second repost. I thus assume the moderators saw the situation in some way already.

Third, OP of the question (the oreseme one) was suspended, this is why they had not points for a while as remarked in another comment. They then apparently wrote email and then created a meta thread including threating with legal action and whatnot, and then where told to leave the site permanently. That meta thread is gone.

Fourth, another relevant meta thread is "trollery." Supposedly this is a group of colleagues of Rhett Butler who was also suspended. (I think there even still more users.) [Added: Possibly "supposedly" is a poor choice of word; what I mean is that this is what these users claim themselves, not that I assume this to be the case.]

Finally, what has this to do with Constantin. I for one consider it as high likely they are part of the group (sign-up same day as OP of question, no other activity besides this one answer and then reposting, except casting many votes, see "trollery" why this is perhaps relevant, and then one other answer when the points where gone). I also said so in a comment to their other answer, leaving open the option that I am wrong. The fact that this is not mentioned in the request for clarification now, is further evidence that they actually know very well why this got deleted. Since if I would not know at all I am suspect of whatever and then somebody would claim I am and strange things happen I might first of all follow up on this or at least also mention it and not say this is all so surprsing.

So, the issue is not with the answer but since they seem to be linked to incorrect activty. Personally I have not enough evidence to be sure and did not flag anything as spam. Some others might see this differently, and if or what the moderators did I cannot know. I hope this clarifies the situation a bit.

Either there are still more accounts of them around, or some people's voting is so extremely strange. The question got a second upvote! The first when the situation was unclear, maybe, I can understand (though also not in fact) but now.

@mellius:

What a funny story.

I am quite sure that everything I wrote is true, though I wrote the text very quickly so there might be some slips. (Please note the clear disticntion I made between what I know and what I believe.)

First of all: no, we are not one and the same. But we know each other.

This is what I reported you claiming.

What about users who have relatives or friends that also are active here?

If you ask me, nothing specific, as long as they interact in reasonable and somewhat transparent ways.

What about users wo in long sequences have earned more than 200 points per day? Pure accident?

I would certainly not consider it as "pure accident". Rather it is a consequence of the quality and quantity of their contributions to the site.

And finally: Where is it laid down that only one account per person is allowed?

It is not the case, in full generality, that only one account per person is allowed.

Isn't this a forum full of people who are used to follow their fixed axioms and rules and nothing else? What a contrast to amateuris detectives who act like despots.

No. There are some general guidelines, supplemented by common sense and courtesy. This is even explicit in the FAQs: "MathOverflow doesn't have formal rules about every possible thing that could come up." However, the current situation resembles earlier ones, IIRC, or at least came up in general dicussions. There is no arbitrariness against you. Personally, I am rather surprised by the general patience you face.

I had not intended to return to this lawless forum full of despotism and arbitriness. But now I will check out whether everybody with enough points has the same right to upvote and downvote. Or whethere some are more equal than others. Let's see.

The FAQs make explcit that not all users are treated the same way (though rather not regarding voting): "If you use a pseudonym and you get into some kind of trouble (e.g. fights in comment threads or spammy-looking posts), the moderators are much less likely to give you the benefit of the doubt."

@mellius: if you knew just how good my life is you might get jealous. I will not follow up on the rest, though'd be somewath tempting.