Abstract
LetS denote the class of schlicht functions. D. Bertilsson proved recently that forf∈S, p<0 and1<-N<-2|p|+1 the modulus of theNth Taylor coefficient of (f′)p takes its maximal value iff is the Koebe function. Here a short proof of a generalisation of this result is presented.
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Wirths, KJ. A short proof of a theorem of Bertilsson by direct use of Löwner’s method. Ark. Mat. 39, 395–398 (2001). https://doi.org/10.1007/BF02384564
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DOI: https://doi.org/10.1007/BF02384564