# Lack of Context: Notation Question

A question I recently answered asked if there was notation for how to write something. It also gave context as to where it came from, but it was closed nonetheless for lack of context, which is understandable seeing as the post was only 2 lines long.

Usually I wouldn't doubt the closing of such a short post, and I agree it could be somewhat improved, but I don't see the possibility for much improvement beyond writing the question outside of the title. I mean, what else can be said when asking for notation outside of the question itself and the context it came from?

The question is terse to an extreme and certainly would benefit from adding a little more detail to the context (for example, drawing out Pascal's triangle and indicating the diagonal entries that sparked interest). You're right, there's not a lot else that can be said about the question; what could be added to make it a better fit (if that's the right word) with the site is enough information for someone to understand it at a glance. As it stands, there's an abstract title and an abstract context and if you're searching for either of those exactly, you're in luck. With a diagram, and some more keywords, more site users can find it when searching, making the question arguably better.

Having written all that though, I agree it should not be closed for lack of context, and not even for lack of effort. I have voted to reopen.

I generally have a pretty low bar for context on questions which are tagged . I think that the simple request for notation is often enough. However, I think that this question fails to meet even that low bar. I have some suggestions:

• A good start would be to move the title into the body of the question. I could do that with an edit, but that is only a start.
• The fact that the "context" isn't even a complete sentence is something I find troubling. For example, as suggested in chat by Martin Sleziak:

Something like: "I often work with expressions like this, since this is exactly the numerator of the binomial coefficient $$\binom nk = \frac{n(n-1)...(n-k+1)}{k!}$$."

• An image showing precisely what feature of Pascal's triangle is being considered would also be helpful.
• Some indication as to where the notation is going to be used. In the fields where I work, the Pochhammer symbol $$(n)_{k}$$ is used. In probability and statistics, I imagine that combinatorial notation given here might be more appropriate. I have heard of the notation $$n^{(k)}$$, $$n^{\overline{k}}$$, and $$n^{\underline{k}}$$, but I honestly don't know the context in which that would be common notation. Knowing where the asker is working would help to provide a good answer. Though, given that the asker seems to have indicated in comments that "all of the above" is a good answer... shrugs
• As postmortes indicates, the question is not very searchable. Expanding the question a bit to give more context would probably help others to find the question.