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arXiv · 1503.01799

Sums of four squares of primes

Angel V. Kumchev·Lilu Zhao
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Abstract

Let $E(N)$ denote the number of positive integers $n \le N$, with $n \equiv 4 \pmod{24}$, which cannot be represented as the sum of four squares of primes. We establish that $E(N)\ll N^{11/32}$, thus improving on an earlier result of Harman and the first author, where the exponent $7/20$ appears in place of $11/32$.

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Angel V. Kumchev, Lilu Zhao. 2015-03-05. Sums of four squares of primes. https://doi.org/10.1112/s0025579315000285

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