@MartinSleziak Honestly, I don't know/remember. It was so long ago (~2009, 2010). Even if they existed, I can't say whether they still exist, considering how much M.SE changed.

Thanks for the response!

BTW I see there is a featured post on meta.MO. IIRC it is quite a long time since the last time there was one.

Happy 5th anniversary, MathOverflow! was featured, as mentioned here in chat.

I guess posts with having some specific-tag in some of past revisions (in this case featured) could be found using SEDE.

Why is mathoverflow.net/questions/43690/whats-a-mathematician-to-do closed?

@MartinSleziak Thank you for the response. I am aware that there is little chance that someone respond to my question. I observed that MO need money to continue running. Therefore it might be MO policy - not to allow too much questions :) Each question need some disk space on the server....

@MarekMitros That's non-sense. IIRC MathOverflow gets the webhosting for free. And the cost of one question is negligible.

I assume you're just joking here, right?

@ma

@MartinSleziak Yes, I am a bit joking. I wonder what is the cost of MO portal which they are collecting money for ? I refer to this meta.mathoverflow.net/questions/3454/… question on meta. I don't quite understand what is "trackbacks to the arXiv" and "citation search" mentioned there.

@MarekMitros I am not sure what you mean by MO portal. As you can see from the post you linked, the webhosting is for free.

> The hosting and maintenance cost of the main MathOverflow site, Meta MathOverflow and the chatrooms hosted on chat.stackexchange.com are covered by Stack Exchange.

Quoted from this answer.

I assume MO still has to pay for the domain name.

To make this more readable for others - the above link goes to: What's a mathematician to do?

I see that you also commented on the question, Marek Mitros.

There are also a few posts tagged trackbacks - if you want to learn more about them.

> I don't quite understand what is "trackbacks to the arXiv" and "citation search" mentioned there.

Probably more experienced users can give you more information. And maybe you'll see more detailed response about the purpose of this as a reaction to Asaf's comment:

@MarekMitros the arXiv is a big preprint server for mathematics. When an article is mentioned on MO, a note is added on the arXiv that it was mentioned on MO. For this to work MO needs to send a notification to arXiv. For doing this there is a standard way called Trackback which is also used by various blogs. However in some way MO still needs to be searched for mention of arXiv papers and to this end some software needs to be maintained and run.

For example this paper:

arxiv.org/abs/math/0408319 (which I chose since I know it was mentioned several times)

when you click on "5 blog links" to the right, you will see that it was mentioned at least five times on MO arxiv.org/tb/math/0408319

That feature is not unique to MO though. Also other blogs and service could be mentioned there.