Gonii: Universal Quaternary Quadratic Forms
نویسندگان
چکیده
We continue our study of quadratic forms using Geometry of Numbers methods by considering universal quaternary positive definite integral forms of square discriminant. We give a small multiple theorem for such forms and use it to prove universality for all nine universal diagonal forms. The most interesting case is x2 + 2y2 + 5z2 + 10w2, which required computer calculations.
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تاریخ انتشار 2011