Carmichael Numbers with a Square Totient

[摘要] Let $varphi$ denote the Euler function. In this paper, we show thatfor all large $x$ there are more than $x^{0.33}$ Carmichael numbers$nle x$ with the property that $varphi(n)$ is a perfect square. Wealso obtain similar results for higher powers.

[学科分类] 数学（综合）

[关键词] Riemann zeta function;Bessel functions;Bourget functions;Dirichlet functions