Four-Vertex Degree Graphs of Nonsolvable Groups
نویسندگان
چکیده
For a finite group G, the character degree graph ∆(G) is the graph whose vertices are the primes dividing the degrees of the ordinary irreducible characters of G, with distinct primes p and q joined by an edge if pq divides some character degree of G. We determine all graphs with four vertices that occur as ∆(G) for some nonsolvable group G. Along with previously known results on character degree graphs of solvable groups, this completes the classification of all four-vertex graphs that occur as ∆(G) for some finite group G.
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