otter software package provides resolution-style theorem prover, you can install in your Ubuntu 14.04 LTS (Trusty Tahr) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install otter
otter is installed in your system.
Make ensure the otter package were installed using the commands given below,
$ sudo dpkg-query -l | grep otter *
You will get with otter package name, version, architecture and description in a table
| Distro | Ubuntu 14 04 lts trusty tahr |
| Section | Mathematics |
| Package | otter |
| Version | 3.3f-1.1 |
| Description | resolution-style theorem prover |
| Sub Section | math |