I need to put a long expression under summation symbol in single row.
For example like this $(i_1,\ldots,i_n)\in\mathcal{P}(\overline{1,n})$
.
How can I get a long summation symbol? Long but not tall.
Minimal working example is
\documentclass{article}
\begin{document}
\[\sum_{(i_1,\ldots,i_n)\in\mathcal{P}(\overline{1,n})}\]
\end{document}
I want summation symbol have same length as string under it. Something like this
But, maybe, I ask something unusual and unapplicable.
\documentclass{...}
and ending with\end{document}
.