\[ \int \frac {1}{\log (x)} \, dx \]
Optimal antiderivative \[ \logarithmicIntegral \left (x \right ) \]
command
Integrate[Log[x]^(-1),x]
Mathematica 13.1 output
\[ \text {li}(x) \]
Mathematica 12.3 output
\[ \int \frac {1}{\log (x)} \, dx \]________________________________________________________________________________________