An irregular assignement of $G$ is labelling $f: E \ra
\{1,2,...,m\}$ of the
edge-set of $G$ such that all of the induced vertex labels computed as
$\sigma_{v\in e}f(e)$ are distinct. The minimal number $m$ for which this
is possible is called the minimal irregularity strength $s_{m}(G)$ of $G$.
The ...
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