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Something is known in considerably greater generality. Let $\|x\|=\min_{n\in\mathbb{Z}}|x-n|$. For $\gamma\in\mathbb{R}-\mathbb{Q}$, define

$$\tau(\gamma) = \sup\Big\{\rho\in\mathbb{R}\colon \liminf_{n\to\infty} n^{\rho}\|\gamma n\|=0\Big\},$$

where the limit inferior is as $n\to\infty$ along the integers. Dirichlet's approximation theorem implies that for all irrational $\gamma$, we have $\tau(\gamma)\geq 1$. Khinchin and Roth proved that $\tau(\gamma)=1$ for almost all real numbers $\gamma$ (in the sense of Lebesgue measure), and $\tau(\gamma)=1$ for all irrational algebraic integers $\gamma$.

If $\gamma>1$ and $\tau(\gamma)<\infty$, then there is an asymptotic prime number theorem that counts the primes of the form $p=\lfloor \gamma n+\beta\rfloor$, where $n\geq 1$ is an integer and $\beta\in\mathbb{R}$ is fixed. A standard source for this is a paper by Banks and Shparlinski.

2734364041
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