I am using Anaconda-Jupyter Notebook on OS: Ubuntu 16.0 for Python programming.
Open a terminal and implement the following commands in it.
$conda install nbconvert
Or
$pip install nbconvert
But I will recommend using conda instead pip if you are using anaconda
$sudo apt-get install pandoc
$sudo apt-get install texlive-xetex
After execution of these commands, close the opened notebooks refresh the home page Or restart the kernel of the opened notebook. Now try to download notebook as a pdf :)
Note: For more details, please refer the official documentation:
https://nbconvert.readthedocs.io/en/latest/install.html