@MartinSleziak I have cast once again duplicate close vote on this one. I am not sure what is the reason the previous close process was invalidated.

A few more comments on questions about last digit(s) in decimal expansion can be found here.

@MartinSleziak Not the same situation, but not entirely unrelated. The review was invalidated after your close vote aged away in this case. So there no longer was a reason to have it in the review.

Thanks for the information, Daniel Fischer. So far I have only seen invalidated when a duplicate was closed in opposite direction.

Good to know that this is also displayed if the vote aged.

@MartinSleziak Basically, whenever something other than the completion of the review removes the reason for the item being in the review queue, the review is invalidated. For example when a post is deleted from outside the review (by its author, by a trusted user voting to delete from the page itself, by a moderator, by a sixth spam/abusive flag), the review is invalidated.

Why it shows negative when person has 2.1k reputation and why is he on last??

@Ramanujan That's the monthly league. The user placed a 500 point bounty on this question on the 5th (unfortunately, that didn't help getting them an answer). Together with only few upvotes they received, that makes a big net reputation loss for the month.

@MartinSleziak Searching for url:www.maths.cam.ac.uk also gives a few questions where we might have outdated links.

For example, maths.cam.ac.uk/undergrad/pastpapers/2009/Part_2/PaperII_3.pdf is dead link, but maths.cam.ac.uk/sites/www.maths.cam.ac.uk/files/pre2014/… - I recently made a similar edit here.

Generally for pdf files it suffices to replace www.math.uga.edu with math.uga.edu. There are som links which also work with www, like math.uga.edu/~pete, math.uga.edu/~pollack, or math.uga.edu/~shifrin.

Sometimes this change is not enough. Some old posts contain math.uga.edu/~pete/expositions.html but math.uga.edu/~pete/expositions.html does not work either.

Hey guys I m concerned about reopening of this question, I think this is an appropriate place: math.stackexchange.com/questions/2064571/…

@THELONEWOLF. I voted to reopen. (But I will not be surprised if it is closed again for the lack of context.) I have also edited the post - I have changed the 23-17 example added by you. AFAIK prime gap usually means gap between two successiveprimes.

Yes @MartinSleziak I saw it, thanks for your kindness. I thought that The prime gap means the difference between any two prime. Thanks

@THELONEWOLF. Well, basically the OP should probably clarify this. I went with the meaning suggested by Wikipedia.

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