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There exist many characterizations for the sporadic
simple groups. In this paper we give two new characterizations for
the Mathieu sporadic groups. Let $M$ be a Mathieu group and $p$ be
the greatest prime advisor of $|M|$. In this paper, we prove that
$M$ is uniquely determined by $|M|$ and $|N_{M}(P)|$, where $P\in
Syl_{p}(M)$. Also, we prove that if $G$ is a finite group, then
$G\cong{M}$ if and only if for every prime $q$,
$|N_{M}(Q)|=|N_{G}(Q^{\prime})|$, where $Q\in Syl_{q}(M)$ and
$Q^{\prime}\in Syl_{q}(G)$.
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