MHB X-like symbol for Cartesian Product (Blyth)

AI Thread Summary
The discussion centers around the challenge of creating a large 'times' symbol for the Cartesian Product in LaTeX, as referenced in T. S. Blyth's book on Module Theory. Participants note that the standard AMS package does not support a \bigtimes command, while \bigotimes is available in MathJax. One user shares a workaround using MathJax to create a large operator symbol with a custom command that utilizes a sans-serif capital X. The provided LaTeX code demonstrates how to define this symbol and compares it to the standard product symbol. Ultimately, there is a consensus that while the custom symbol can be created, it may be preferable to use the conventional product symbol \prod for clarity and consistency.
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In T. S. Blyth's book on Module Theory, the author uses a large 'times' symbol (similar to a capital X) for the Cartesian Product as seen in the text below (taken from Blyth page 58)
View attachment 3458Can someone help me with the Latex code for such a symbol?Peter
 
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Hmm, I've been reading up on this for a little bit now and it might be that this isn't possible with the normal AMS package.

There is a \bigotimes command that works with Mathjax but \bigtimes doesn't.

$$\bigotimes$$

Here is a SE post about this topic. Maybe someone else can find a solution. :)
 
Jameson said:
Hmm, I've been reading up on this for a little bit now and it might be that this isn't possible with the normal AMS package.

There is a \bigotimes command that works with Mathjax but \bigtimes doesn't.

$$\bigotimes$$

Here is a SE post about this topic. Maybe someone else can find a solution. :)

Thanks Jameson ... yes, I experimented with \bigtimes as well ...

Pity that there appears to be no solution to this ...

Peter
 
Using MathJax, the best I can do is $$\mathop{\vcenter{\huge\times}}_{i=1}^n x_i$$. If you are using a complete implementation of LaTeX, I found a useful post here showing how to use a Maltese cross as a large operator symbol. I adapted that to use with a large sansserif capital X, and I found that this works very well. The code
Code:
\documentclass{article}
\begin{document}
\newcommand{\xprod}{%
  \mathop{ %
    \mathchoice{\dobigx\huge}
               {\dobigx\Large}
               {\dobigx\normalsize}
               {\dobigx\small}
    }
}
\newcommand{\dobigx}[1]{%
  \vcenter{\kern.2ex\hbox{\sffamily#1X}\kern.2ex}}
Here it is in text, with the usual product symbol for comparison: $\xprod_{i=1}^n x_i$, $\prod_{i=1}^n x_i$. In display style, it looks like
\[
\xprod_{i=1}^n x_i \qquad \prod_{i=1}^n x_i
\]
\end{document}
produced this output:

View attachment 3465

In practice, I think it is much better to stick with the usual product symbol $$\prod.$$
 

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