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Let G be a finite group, Irr(G) the set of all irreducible complex characters of G and x in Irr(G). Let also
cod(x) = |G : kerx|=x(1) and cod(G) = {cod(x)| x $\in$ Irr(G)}. In this note, we show that the simple group
PSL(2; q), for a prime power q > 3, is uniquely determined by the set of its codegree.
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