Yamamoto's reciprocity law

In mathematics, Yamamoto's reciprocity law is a reciprocity law related to class numbers of quadratic number fields, introduced by Yamamoto (1986).

References

• Williams, Kenneth S. (1991), "On Yamamoto's reciprocity law", Proceedings of the American Mathematical Society 111 (3): 607–609, doi:10.2307/2048395, ISSN 0002-9939, MR 1047009 
• Yamamoto, Yoshihiko (1986), "Congruences modulo 2ⁱ (i=3,4) for the class numbers of quadratic fields", Proceedings of the international conference on class numbers and fundamental units of algebraic number fields (Katata, 1986), Nagoya: Nagoya Univ., pp. 205–215, MR 891897