The Oracle R Distribution 3.1.1 binaries for Windows, AIX, Solaris SPARC and Solaris x86 are now available on OSS, Oracle's Open Source Software portal. Oracle R Distribution 3.1.1 is an update to R version 3.1.0, and it includes many improvements, including upgrades to the package help system and improved accuracy importing data with large integers. The complete list of changes is in the NEWS file.
To install Oracle R Distribution, follow the instructions for your platform in the Oracle R Enterprise Installation and Administration Guide.