Adding to Eric Naslund's comment: Let $\pi(x)$ denote the number of primes less than $x$, then Montgomery & Vaughan proved that $$ \pi(x+y)-\pi(x) \le 2 \pi(y)$$ for $x\ge 1$ and $y\ge 2.$
Micah Milinovich
- 5k
- 1
- 31
- 41