Often you need a notation for a finite sequence with one element is removed;
i.e. $$(x_1,\dots,x_{i-1},x_{x+1}\dots, x_n).$$
I know one notation
$$(x_1,\dots,\hat x_i,\dots, x_n)$$
and I hate it. It is too long and it has no sense; i.e., unless you know the meaning you will never guess what is it.

**Question:** Did you see any other?