3

I want to create

enter image description here

For this, I write

\begin{equation*}  
\sum^* =\sum^0 \cup\sum^1 \cup \sum^2 \cup\ldots  
\end{equation*}

But this creates

enter image description here

Again if I write this in inline mode like

$\sum^* =\sum^0 \cup\sum^1 \cup \sum^2 \cup\ldots$

then it gives

enter image description here

Why is this happening? Because I want to write this in equation* environment.

Mico
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Manjoy Das
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    \sum is for a summation, so superscripts should go above. Are you perhaps wanting \Sigma? – Teepeemm May 02 '21 at 19:00
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    Note that, as a cheat, if you really want to use \sum, you can type {\sum}^* ={\sum}^0 \cup {\sum}^1 \cup {\sum}^2 which produces what you're looking for. But the LaTeX police should be here in a minute ;) – SebGlav May 02 '21 at 19:04
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    @SebGlav and the punishments? :D – Manjoy Das May 02 '21 at 19:59
  • @ManjoyDas Reading War and Peace typeset in Comic Sans. :-D – egreg May 02 '21 at 22:15

1 Answers1

5

If I understand your typesetting needs correctly, you should be using \Sigma rather than \sum, and \dotsb rather than \ldots.

enter image description here

However, I will readily concede that I may not have correctly understood what you're trying to achieve.

\documentclass{article}
\usepackage{amsmath} % for 'equation*' env. and '\dotsb' macro
\begin{document}

\begin{equation}
\Sigma^ =\Sigma^0 \cup \Sigma^1 \cup \Sigma^2 \cup \dotsb
\end{equation*}


\end{document}
Mico
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  • the difference between \ldots and \dotsb? – Manjoy Das May 02 '21 at 19:54
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    @ManjoyDas I would recommend reading through the AMS math documentation. \ldots is "lowered dots" (as opposed to "centered"). \dotsb is "dots in place of a binary operator". The default will look like the \cdots you want, but this way, a journal could redefine \dotsb according to their preference. – Teepeemm May 02 '21 at 19:59
  • @ManjoyDas - The difference between \ldots and \dotsb should be evident if you compare (a) the 2nd and 3rd screenshots of your posting and (b) either my code or the 1st screenshot in your posting. – Mico May 02 '21 at 20:15