Logarithmic integral
From specialfunctionswiki
The logarithmic integral is $$\mathrm{li}(x) = \displaystyle\int_0^x \dfrac{dt}{\log(t)},$$ where $\log$ denotes the logarithm. The logarithmic integral is related to the exponential integral by the formula $$\mathrm{li}(x)=\mathrm{Ei}( \log(x)).$$
- Logarithmicintegral.png
Graph of $\mathrm{li}$ on $[0,6]$.
Contents
Properties
Theorem
The following formula holds: $$\lim_{x \rightarrow \infty} \dfrac{\pi(x)}{\mathrm{li}(x)}=1,$$ where $\pi$ denotes the prime counting function and $\mathrm{li}$ denotes the logarithmic integral.
