Directory macros/latex2e/contrib/12many

In the discrete branches of mathematics and the computer sciences, it
will only take some seconds until you're faced with a set like
$\{1,\ldots,m\}$. Only some people write $1\ldotp\ldotp m$, or
$\{j:1\leq j\leq m\}$, and that journal you're submitting to might
want something else entirely. \otm{} provides an interface that makes
changing from one to another a one-line change.