Just today, we had the following situation:

Proving by induction that $n^{n+1} > (n+1)^n$ for $n \ge 3$

Prove by induction that for all $n \geq 3$: $n^{n+1} > (n+1)^n$

Usually, I can see some merit in keeping duplicates for indexing and visibility purposes. But in the above case, it seems very reasonable that (perhaps on some longer term) these questions be merged, because such benefits are absent.


Some search did not reveal any information on:

  • What the requirements/guidelines for merging questions are (this includes a time perspective -- how old do we need the questions to be before merging);
  • How one can bring merging candidates meeting these requirements to the attention of moderators.

Thoughts and suggestions are appreciated, as well as "official" response.


Usually, when a question has been closed as a duplicate of another, a moderator can merge the questions, if warranted. If the question was closed by community votes, then the question can be flagged to get moderator attention.

Although a question may be classified as an "exact duplicate", it may not be suitable for merging since the answers to one may not serve as answers to the other, due to subtle differences in the question.

e.g. the older question would admit both inductive proofs and proofs using the binomial theorem, whereas the newer question asks specifically for induction. Thus, the newer question can be merged into the older (but not vice versa).

  • $\begingroup$ Thank you, robjohn. Just two further questions: Is it sufficient to rely on one's gut feeling for when questions should be merged? Should one wait for some time before flagging? $\endgroup$
    – Lord_Farin
    May 30 '13 at 13:01
  • 2
    $\begingroup$ If all the answers to one question would serve as answers to the other question, then the questions should probably be merged. You may flag if you feel this is the case. However, the moderator reviewing the flag may feel differently. $\endgroup$
    – robjohn Mod
    May 30 '13 at 13:17
  • 7
    $\begingroup$ It is important that said answers should be an answer to the other question exactly as written. If the two questions use drastically different notations, merging the answers can sometimes cause confusion. $\endgroup$ May 30 '13 at 14:29
  • $\begingroup$ If I may ask, is there any problem merging questions that both do not have sufficient answers to answer the questions but will likely help both a lot? I am trying to merge this and this. $\endgroup$ Feb 1 '17 at 23:18
  • 2
    $\begingroup$ @SimplyBeautifulArt: both of those questions look to be the same. It seems to me that any answer to one would answer the other. $\endgroup$
    – robjohn Mod
    Feb 2 '17 at 3:25

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .