Nonsolvable Groups with Three Nonlinear Irreducible Character Codegrees

Abstract

For an irreducible character χ of a finite group G, the codegree of χ is defined as ∣G: ker(χ)∣/χ(1). In this paper, the authors determine finite nonsolvable groups with exactly three nonlinear irreducible character codegrees, which are L₂(2 ^f) for f ≥ 2, PGL₂(q) for odd q ≥ 5 or M₁₀.

Keywords

Character codegree / Nonsolvable group

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