May I use comma to avoid redundancy in expressions?

Question

Is it generally possible to write $$1\leq k,l\leq 8$$ instead of $$1\leq k\leq8\quad \mathrm{and} \quad 1\leq l\leq 8$$ to avoid redundancy?

Answer 1

Absolutely, a lot of people do it all the time.

Just be careful to avoid confusion between

$$1\leq l,k\leq 8$$

and

$$1\leq l<k\leq 8.$$

Answer 2

Yes, but be sure that the space after the comma is thin (which is the TeX default). Thus, if we were to write (rather unnaturally) "$1\leqslant k,\;$ $l\leqslant8,\;$ and $m\leqslant3$", the reader would be uncertain as to whether the restrictions on $k$ and $l$ applied respectively or to both.