# Notation for unordered product of sets

Frequently, when referring to the edges of an undirected graph $G=(V,E)$, I want to write that $E \subset V \times V$, which isn’t correct since the Cartesian product is ordered and the edges are not.

This motivates my question: is there a common notation for a product of sets $A$ and $B$ defined by $\{ \{a,b\} ~|~ a \in A ,~ b \in B \}$?

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I use $E \subseteq \binom{V}{2}$. Although, I have seen it used elsewhere, it’s probably not a standard notation.

We used $\bar{\times}$ (but without the gap between the bar and the times symbol) in the algebraic graph theory lectures I’ve attended some years ago. I liked it, however I don’t know how common it is.