Editing Logarithmic integral function (section)

== Special values ==
The function li(''x'') has a single positive zero; it occurs at ''x'' ≈ 1.45136 92348 83381 05028 39684 85892 02744 94930... {{OEIS2C|A070769}}; this number is known as the [[Ramanujan–Soldner constant]].

<math>\operatorname{li}(\text{Li}^{-1}(0)) = \text{li}(2)</math> ≈ 1.045163 780117 492784 844588 889194 613136 522615 578151... {{OEIS2C|A069284}}

This is <math>-(\Gamma(0,-\ln 2) + i\,\pi)</math> where <math>\Gamma(a,x)</math> is the [[incomplete gamma function]]. It must be understood as the [[Cauchy principal value]] of the function.