Satoh, Junya The Iwasawa \(\lambda{}_ p\)-invariants of \(\Gamma\)-transforms of the generating functions of the Bernoulli numbers. (English) Zbl 0739.11047 Jap. J. Math., New Ser. 17, No. 1, 165-174 (1991). We quote the author’s words: “We give an elementary proof of Kida’s formula on Hurwitz-type relations of cyclotomic \(\lambda_ p\)-invariants of abelian number fields, using the theory of \(\Gamma\)-transforms of rational functions. Our proof will be carried out only in terms of rational functions”. Reviewer: K.Lakkis (Thessaloniki) MSC: 11R23 Iwasawa theory 11R20 Other abelian and metabelian extensions Keywords:Hurwitz relations; Kida’s formula; cyclotomic \(\lambda_ p\)-invariants; abelian number fields PDFBibTeX XMLCite \textit{J. Satoh}, Jpn. J. Math., New Ser. 17, No. 1, 165--174 (1991; Zbl 0739.11047)