# Double subscript issue

How can I write (Jx)x∈A in LaTeX? (the second subscript is for parentheses.)

I am trying to write like this, but it's not working: (J}_x)_{x_\in_\textit{A}

Thank you!

• Hm, difficult to see, what you like to obtain. Maybe $J(x)_{x\in A}$ (this very unusual notation)? I only guessing ... And of course: Welcome to SE!. Jan 4, 2016 at 20:09
• Well @Zarko, I've already seen that notation for mathematical sequences but with u,n and N not J,x and A so yes that's quite strange in fact! Jan 4, 2016 at 20:22
• @PMC1234, to me is more logical $J(x\in A)$ or $J_{x}\big|_{x\in A}$, however, different topics areas, different habits ... Jan 4, 2016 at 20:25
• Yeah! I got a look on Wikipedia and it differs from countries ! In France we use this notation (u_n)_n\inN, and in anglophone countries they use yours ! Jan 4, 2016 at 20:28
• I very rarely read french literature (only with lot of pictures, they doesn't require language knowledge :-) ), so in OP question is actually wrong the first} after letter J. She only need to remove it. Jan 4, 2016 at 20:31

Try out ${(J_x)}_{x\in A}$. It works with me.

• You are completely right! But when it tends to be separated expressions, they are mandatory so, let's use them every time :-) Jan 4, 2016 at 20:19

Well, I will obey Barbara Beeton suggestion:

• in your code are misplaced curly braces and use of _: instead of (J}_x)_{x_\in_\textit{A} it should be $(J_x)_{x\in\textit{A}}$ or simpler $(J_x)_{x\in A}$
• your notation is very unusual, to me is more logical $J(x\in A)$ or $J_{x}\big|_{x\in A}$ or even $J_{x\in A}$.

See examples below:

\documentclass{article}

\usepackage[active,tightpage]{preview}
\setlength\PreviewBorder{1em}

\begin{document}
%---------------------------------------------------------------%
\begin{preview}
\begin{tabular}{rl}
\verb+$(J_x)_{x\in A }$+: &    $(J_x)_{x\in A}$\\
\verb+$J(x\in A)$+:              &  $J(x\in A)$\\
\verb+$J_{x}\big|_{x\in A}$+:    &  $J_{x}\big|_{x\in A}$\\
\verb+$J_{x\in A}$+:             &  $J_{x\in A}$
\end{tabular}
\end{preview}
%---------------------------------------------------------------%
\end{document}
` 