The current LAMMPS tarball on SourceForge is the 31 Mar 2017 version.
Newer development LAMMPS tarballs are available for download from the
LAMMPS web site at lammps.sandia.gov or from GitHub at
https://github.com/lammps/lammps. The 31Mar17 version is a stable
version within the last year. There may be newer stable versions on
the web site or GitHub.
All documentation for LAMMPS is available on the LAMMPS web site.
All questions about LAMMPS should be posted to the LAMMPS mail list
(hosted by SourceForge); see lammps.sandia.gov/mail.html for info on
how to join the list, post to it, browse and search past threads, etc.
The SourceForge Forums for LAMMPS are NOT read by the LAMMPS
developers. Post questions to the mail list instead.