A necessary and sufficient condition is given for the ideal class group H( m } of a real quadratic field Q (m)to contain a cyclic subgroup of order n.Some criteria satisfying the condition are also obtained.And eight ...A necessary and sufficient condition is given for the ideal class group H( m } of a real quadratic field Q (m)to contain a cyclic subgroup of order n.Some criteria satisfying the condition are also obtained.And eight types of such fields are proved to have this property,e.g.fields with m=(zn+t+12)+4t(with t|zn-1),which contains the well-known fields with m=4zn+1 and m=z2n+4 as special cases.展开更多
Necessary and sufficient condition on real quadratic algebraic function fields K is given for theirideal class groups H(K) to contain cyclic subgroups of order n. And eight series of such real quadratic functionfields...Necessary and sufficient condition on real quadratic algebraic function fields K is given for theirideal class groups H(K) to contain cyclic subgroups of order n. And eight series of such real quadratic functionfields K are obtained whose ideal class groups contain cyclic subgroups of order n. In particular, the ideal classnumbers of these function fields are divisible by n.展开更多
Series of results about ideal class groups H （m） and class numbers h （m） of real quadratic fields Q (m<sup>1/2</sup>) can be obtained from [6]. Some of them will be shown in this note. We denote by C&l...Series of results about ideal class groups H （m） and class numbers h （m） of real quadratic fields Q (m<sup>1/2</sup>) can be obtained from [6]. Some of them will be shown in this note. We denote by C<sub>n</sub> =Z/nZ the cyclic group of order n. Let m ∈ Z denote a square free positive integer, and let z<sub>1</sub>, z, t ∈Z be arbitrary integers with z<sub>1</sub> odd and t】0.展开更多
Under the generalized Riemann hypothesis, it is proved that the Diophantine equation xy + yz + zx = m always has a solution except for 18 positive integers m.
Let E / K be an elliptic curve with K-rational p-torsion points. The p-Selmer group of E is described by the image of a map uK and hence an upper bound of its order is given in terms of the class numbers of the S-idea...Let E / K be an elliptic curve with K-rational p-torsion points. The p-Selmer group of E is described by the image of a map uK and hence an upper bound of its order is given in terms of the class numbers of the S-ideal class group of K and the p-division field of E.展开更多
In this paper, we study the real quadratic function fields K=k(D), given a necessary and sufficient condition for the ideal class group H(K) of any real quadratic function field K to have a cyclic subgroup of order n,...In this paper, we study the real quadratic function fields K=k(D), given a necessary and sufficient condition for the ideal class group H(K) of any real quadratic function field K to have a cyclic subgroup of order n, and obtained eight series of such fields. The ideal class numbers h(O K) of K in the series all have a factor n.[展开更多
Imaginary cyclic fields of degree p-1 which have two distinct unramified cyclic extensions of degree p are produced using elementary properties of the Lucas sequences. An infinite family of imaginary cyclic fields of ...Imaginary cyclic fields of degree p-1 which have two distinct unramified cyclic extensions of degree p are produced using elementary properties of the Lucas sequences. An infinite family of imaginary cyclic fields of degree p-1 are then given with the p-rank of the ideal class groups of at least two.展开更多
A necessary condition is presented for the ideal class group of an imaginary quadratic function field K=k(D) (k=F-q(x), 2q) to be of exponent ≤2. The condition is proved to be sufficient in some cases. An analogue of...A necessary condition is presented for the ideal class group of an imaginary quadratic function field K=k(D) (k=F-q(x), 2q) to be of exponent ≤2. The condition is proved to be sufficient in some cases. An analogue of Louboutin’s result in function field case is particularly presented.展开更多
基金Project supported by the National Natural Science Foundation of China.
文摘A necessary and sufficient condition is given for the ideal class group H( m } of a real quadratic field Q (m)to contain a cyclic subgroup of order n.Some criteria satisfying the condition are also obtained.And eight types of such fields are proved to have this property,e.g.fields with m=(zn+t+12)+4t(with t|zn-1),which contains the well-known fields with m=4zn+1 and m=z2n+4 as special cases.
基金This work was supported by the National Natural Science Foundation of China(Grant No.10071041).
文摘Necessary and sufficient condition on real quadratic algebraic function fields K is given for theirideal class groups H(K) to contain cyclic subgroups of order n. And eight series of such real quadratic functionfields K are obtained whose ideal class groups contain cyclic subgroups of order n. In particular, the ideal classnumbers of these function fields are divisible by n.
文摘Series of results about ideal class groups H （m） and class numbers h （m） of real quadratic fields Q (m<sup>1/2</sup>) can be obtained from [6]. Some of them will be shown in this note. We denote by C<sub>n</sub> =Z/nZ the cyclic group of order n. Let m ∈ Z denote a square free positive integer, and let z<sub>1</sub>, z, t ∈Z be arbitrary integers with z<sub>1</sub> odd and t】0.
文摘Under the generalized Riemann hypothesis, it is proved that the Diophantine equation xy + yz + zx = m always has a solution except for 18 positive integers m.
文摘Let E / K be an elliptic curve with K-rational p-torsion points. The p-Selmer group of E is described by the image of a map uK and hence an upper bound of its order is given in terms of the class numbers of the S-ideal class group of K and the p-division field of E.
文摘In this paper, we study the real quadratic function fields K=k(D), given a necessary and sufficient condition for the ideal class group H(K) of any real quadratic function field K to have a cyclic subgroup of order n, and obtained eight series of such fields. The ideal class numbers h(O K) of K in the series all have a factor n.[
基金Supported by the Japan Society for the Promotion of Science (JSPS) (No. 14540030) the JSPS Research Fellowships for Young Scientists
文摘Imaginary cyclic fields of degree p-1 which have two distinct unramified cyclic extensions of degree p are produced using elementary properties of the Lucas sequences. An infinite family of imaginary cyclic fields of degree p-1 are then given with the p-rank of the ideal class groups of at least two.
文摘A necessary condition is presented for the ideal class group of an imaginary quadratic function field K=k(D) (k=F-q(x), 2q) to be of exponent ≤2. The condition is proved to be sufficient in some cases. An analogue of Louboutin’s result in function field case is particularly presented.
