Hilbert genus fields of real biquadratic fields
Tóm tắt
The Hilbert genus field of the real biquadratic field 
                  
                    
                  
                  $$K=\mathbb {Q}(\sqrt{\delta },\sqrt{d})$$
                  
                    
                  
                 is described by Yue (Ramanujan J 21:17–25, 2010) and by Bae and Yue (Ramanujan J 24:161–181, 2011) explicitly in the case 
                  
                    
                  
                  $$\delta =2$$
                  
                    
                  
                 or 
                  
                    
                  
                  $$p$$
                  
                    
                  
                 with 
                  
                    
                  
                  $$p\equiv 1 \, \mathrm{mod}\, 4$$
                  
                    
                  
                 a prime and 
                  
                    
                  
                  $$d$$
                  
                    
                  
                 a squarefree positive integer. In this article, we describe explicitly the case that 
                  
                    
                  
                  $$\delta =p, 2p$$
                  
                    
                  
                 or 
                  
                    
                  
                  $$p_1p_2$$
                  
                    
                  
                 where 
                  
                    
                  
                  $$p$$
                  
                    
                  
                , 
                  
                    
                  
                  $$p_1$$
                  
                    
                  
                , and 
                  
                    
                  
                  $$p_2$$
                  
                    
                  
                 are primes congruent to 
                  
                    
                  
                  $$3$$
                  
                    
                  
                 modulo 
                  
                    
                  
                  $$4$$
                  
                    
                  
                , and 
                  
                    
                  
                  $$d$$
                  
                    
                  
                 is any squarefree positive integer, thus complete the construction of the Hilbert genus field of real biquadratic field 
                  
                    
                  
                  $$K=K_0(\sqrt{d})$$
                  
                    
                  
                 such that 
                  
                    
                  
                  $$K_0=\mathbb {Q}(\sqrt{\delta })$$
                  
                    
                  
                 has an odd class number.
Tài liệu tham khảo
Bae, S., Yue, Q.: Hilbert genus fields of real biquadratic fields. Ramanujan J. 24, 161–181 (2011)
Conner, P.E., Hurrelbrink, J.: Class Number Parity, Ser. Pure Math., vol. 8. World Scientific, Singapore (1988)
Lang, S.: Cyclotomic Fields I and II. GTM 121. Springer-Verlag, New York (1990)
McCall, T.M., Parry, C.J., Ranalli, R.R.: On imaginary bicyclic biquadratic fields with cyclic 2-class group. J. Number Theory 53, 88–99 (1995)
Ouyang, Y., Zhang, Z.: Hilbert genus fields of biquadratic fields. Sci. China Math., to appear
Sime, P.: Hilbert class fields of real biquadratic fields. J. Number Theory 50, 154–166 (1995)
Yue, Q.: The generalized Rédei matrix. Math. Z. 261, 23–37 (2009)
Yue, Q.: Genus fields of real biquadratic fields. Ramanujan J. 21, 17–25 (2010)
Zhang, Z., Yue, Q.: Fundamental units of real quadratic fields of odd class number. J. Number Theory 137, 122–129 (2014)
