Take the 2-minute tour ×
Mathematics Stack Exchange is a question and answer site for people studying math at any level and professionals in related fields. It's 100% free, no registration required.

I want to describe a vector of n length, where each element is described by it's index. What is the correct notation?

As it is now, to describe the vector [ 1 4 9 16 ] i write:


But I can't remember if this is something i made up in my own mind.

share|improve this question
I think you mean [1 4 9 16]... –  Jesse Madnick Apr 14 '11 at 8:19
Using $\{ \ldots \}$ would suggest a set. You should use $( \ldots )$ instead. –  Zhen Lin Apr 14 '11 at 9:13

1 Answer 1

I will advise you to write $\mathbf{a} = (a_1,...,a_4 )$ where $a_i = i^2$. A little bit longer but correct.

share|improve this answer
This is actually the notation I am trying to avoid since it has become very unpractical when dealing with a lot of vectors. Is my shorter notation wrong? –  user8111 Apr 14 '11 at 8:39
@Marc: What context do you want to use the notation in? Notations are largely invented for convenience, if it's convenient to you, it's a good notation. The only qualm a mathematician could have with it is the curly brackets which usually serve to denote sets. If you replace them by normal round brackets, that should be fine. –  Raskolnikov Apr 14 '11 at 9:02
I see, thanks for the help! –  user8111 Apr 14 '11 at 9:18
I also advise you to predefine this notation in the form with an explanation of the notation and then use the notation which you need. –  Ilya Apr 14 '11 at 9:28

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.