Notation to describe vector

Question

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:

$\{a^{2}\}_{a=1}^{4}$

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

Using ${ \ldots }$ would suggest a set. You should use $( \ldots )$ instead. — Zhen Lin, Apr 14 '11 at 09:13

score 3 · Answer 1 · answered Apr 14 '11 at 08:18

3

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

answered Apr 14 '11 at 08:18

SBF

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? – Apr 14 '11 at 08:39
1

@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 09:02
I see, thanks for the help! – Apr 14 '11 at 09:18
2

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. – SBF Apr 14 '11 at 09:28

1 Answers1