Quasirecognition by Prime Graph of the Groups
نویسندگان
چکیده
Let G be a finite group. The prime graph Γ(G) of G is defined as follows: The set of vertices of Γ(G) is the set of prime divisors of |G| and two distinct vertices p and p′ are connected in Γ(G), whenever G has an element of order pp′. A non-abelian simple group P is called recognizable by prime graph if for any finite group G with Γ(G) = Γ(P ), G has a composition factor isomorphic to P . In [4] proved finite simple groups Dn(q), where n 6= 4k are quasirecognizable by prime graph. Now in this paper we discuss the quasirecognizability by prime graph of the simple groups D2k(q), where k ≥ 9 and q is a prime power less than 10.
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