Short proofs of the universality of certain diagonal quadratic forms
نویسنده
چکیده
In a paper of Kim, Chan, and Rhagavan, the universal ternary classical quadratic forms over quadratic fields of positive discriminant were discovered. Here a proof of the universality of some of these quadratic forms is given using a technique of Liouville. Another quadratic form over the field of discriminant 8 is shown universal by a different elementary approach. Mathematics Subject Classification (2000). Primary 11E25, 11D57, 11P05.
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