2-universal Positive Definite Integral Quinary Quadratic Forms
نویسندگان
چکیده
As a generalization of the famous four square theorem of Lagrange, Ramanujan and Willerding found all positive definite integral quaternary quadratic forms that represent all positive integers. In this paper, we find all positive definite integral quinary quadratic forms that represent all positive definite integral binary quadratic forms. We also discuss recent results on positive definite integral quadratic forms which represent all positive integral quadratic forms in three or more variables.
منابع مشابه
2-universal Positive Definite Integral Quinary Diagonal Quadratic Forms
As a generalization of the famous four square theorem of Lagrange, Ramanujan found all positive definite integral quaternary diagonal quadratic forms that represent all positive integers. In this paper, we find all positive definite integral quinary diagonal quadratic forms that represent all positive definite integral binary quadratic forms. §
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