I am new to writing mathematics papers, and often times I have the need to express an idea for which there is no standard mathematical convention (or if there is, may be too tedious to do formally).
Consider the following definition of a set of the $n^{th}$ root of unity, raised to the power $k \in \{0,1,2,\dots,n-1\}$. It seems natural to me to express this set in the following way
$$ \{\omega_n^k\}_{k=0}^{n-1} $$
Although, this makes me wonder when it is acceptable to use notation which is not particularly standard. At least, I have not seen the form above, but I do anticipate the meaning should be clear to the reader.
Is there a consensus or reference book for notation, or does one pick it up from the literature?