# Interesting sequence mod p

Number Theory Level pending

Let $$x_{n}$$ be a sequence of positive integers with $$x_{1}=1$$ and for any prime number $$p$$ the set $$\{x_{1},x_{2},...,x_{p}\}$$ is a complete residue system $$\pmod{p}$$. Then what is the value of the limit $\lim_{n \to \infty} \frac{a_{n}}{n} - \frac{3}{4}$

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