PRIME-UNIVERSAL QUADRATIC FORMS $ax^{2}+by^{2}+cz^{2}$ AND $ax^{2}+by^{2}+cz^{2}+dw^{2}$
Sign Up to like & getrecommendations! Published in 2019 at "Bulletin of the Australian Mathematical Society"
DOI: 10.1017/s0004972719001023
Abstract: A positive-definite diagonal quadratic form $a_{1}x_{1}^{2}+\cdots +a_{n}x_{n}^{2}\;(a_{1},\ldots ,a_{n}\in \mathbb{N})$ is said to be prime-universal if it is not universal and for every prime $p$ there are integers $x_{1},\ldots ,x_{n}$ such that $a_{1}x_{1}^{2}+\cdots +a_{n}x_{n}^{2}=p$ . We… read more here.
Keywords: universal quadratic; quadratic forms; forms prime; prime universal ... See more keywords