This image is an example of what I want to get.

https://www.dropbox.com/s/dmqd0nt0thg5u ... o.png?dl=0
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\documentclass{article}\usepackage{xcolor}\newcommand{\inlinemath}[1]{\fcolorbox{red}{white}{\ensuremath{#1}}}\begin{document}In what follows we use the following notation: if \inlinemath{S},\inlinemath{T \subseteq N}, \inlinemath{z=(z_i)_{i \in N}} is an $n$-vector, and\dots\end{document}
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