Central superscripts and subscripts with any letter or symbol

Question

I'm trying to write the following in Notion (using KaTeX library):

The closest thing I've got is with this code:

L_{DNI} = \left( \text{U}_{i=1}^{8} \right) L_A

I would like to do the same with others letters like A,B or the intersection symbol(∩). Any idea?

Edit:

I've found the solution before this post by myselft but i want to share with the community.

Just using underset and overset can be done easily:

L_{DNI} = \left( \overset{8}{\underset{i=1}{\text{U}}} \right) L_A

You can replace the text field section with anything:

If you try with Unicode symbols doesn't work well:

Answer 1

Like this?

\documentclass[a4paper,12pt]{article}
\usepackage{amsmath,amssymb}
\begin{document}
\[L_{\textup{DNI}} = \left( \bigcup^{8}_{i=1} \right) L_A\]
\end{document}

\documentclass[a4paper,12pt]{article}
\usepackage{amsmath,amssymb}
\begin{document}
[L_{\textup{DNI}} = \left( \bigcup^{8}{i=1} L{D}\right) L_A]
\end{document}

\documentclass[a4paper,12pt]{article}
\usepackage{amsmath,amssymb}
\begin{document}
[L_{\textup{DNI}} = \left( \bigcap^{8}{i=1} L{D}\right) L_A]
\end{document}