I am searching fo an appropriate symbol in latex for the concatenation between two sets
Thanks,
I want a symbol like this in the following 
image
[Tex/LaTex] Concatenation symbol between two sets
symbols
Related Solutions
Since a vector in R^2 is written (1, 2), it would make sense to concatenate two vectors a and b as (a,b).
You want to use \bigoplus instead of \oplus.
I've never seen concatenation done that way. Addition and XOR are commutative operations so it makes sense to sum over a set (or take the exclusive OR of a set). Concatenation is not like that. I think I would explicitly write out the concatenation. That said, you can use \bigparallel from the stmaryrd package.
\documentclass{article}
\usepackage{amsmath}
\usepackage{stmaryrd}
\newcommand*\concat{\mathbin{\|}}
\begin{document}
\[x_1\concat x_2\concat\dotsb\concat x_n\]
\[\bigparallel_{i=1}^n x_i\]
\end{document}
Best Answer
A great resource for this kind of question is the opaquely named Detexify, at http://detexify.kirelabs.org/classify.html. You sketch a shape with the mouse and it lists the TeX symbols that look like it, along with package and mode information. It did a great job with my very clumsy rendering of your symbol, finding as top matches the same symbols proposed by egreg and LaRiFaRi: