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http://dx.doi.org/10.4134/JKMS.j200290

EVEN 2-UNIVERSAL QUADRATIC FORMS OF RANK 5  

Ji, Yun-Seong (Research Institute of Mathematics Seoul National University)
Kim, Myeong Jae (Department of Mathematical Sciences Seoul National University)
Oh, Byeong-Kweon (Department of Mathematical Sciences Seoul National University)
Publication Information
Journal of the Korean Mathematical Society / v.58, no.4, 2021 , pp. 849-871 More about this Journal
Abstract
A (positive definite integral) quadratic form is called even 2-universal if it represents all even quadratic forms of rank 2. In this article, we prove that there are at most 55 even 2-universal even quadratic forms of rank 5. The proofs of even 2-universalities of some candidates will be given so that exactly 20 candidates remain unproven.
Keywords
Even 2-universal quadratic form;
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