TY - JOUR T1 - Characterizations of the simple group $D_{n}(3)$ by prime graph and spectrum TT - JF - IJMSI JO - IJMSI VL - 7 IS - 1 UR - http://ijmsi.ir/article-1-306-en.html Y1 - 2012 SP - 91 EP - 106 KW - Characterization KW - prime graph KW - the classification theorem of finite simple group KW - spectrum. N2 - We prove that $D_n(3)$, where $ngeq6$ is even, is uniquely determined by its prime graph. Also, if $G$ is a finite group with the same prime graph as $D_4(3)$, then $Gcong D_4(3), B_3(3), C_3(3)$ or $G/O_2(G)cong {rm Aut}({}^2B_2(8))$. M3 10.7508/ijmsi.2012.01.009 ER -