Well-behaved Beurling primes and integers

In this paper, we study generalised prime systems for which both the prime and integer counting functions are asymptotically well-behaved, in the sense that they are approximately li(x) and ρx, respectively (where ρ is a positive constant), with error terms of order O(x^θ₁) and O(x^θ₂) for some θ₁,θ₂<1. We show that it is impossible to have both θ₁ and θ₂ less than .