Whether on or off-campus
Be sure the vpn-groups portal is selected when you connect.

$ module avail Mathematica
--- /data/Apps/Modules/Programming ---
Mathematica/11.3.0  Mathematica/12.0 Mathematica/12.1  

$ module load Mathematica

$ module list
Currently Loaded Modulefiles:
1) Mathematica/11.3.0

#!/usr/bin/bash
#PBS -N mathematica_job
#PBS -l nodes=1:ppn=24
#PBS -l walltime=01:00:00
#PBS -m abe                    ## mail on abort, begin and error
#PBS -M [email protected]
#PBS -j oe                        ## same file for output and error

JOBID=$( echo ${PBS_JOBID} | cut -f1 -d. )

## load the Mathematica module
module load Mathematica

## set up any needed variables, paths and files
## run your job

math -noprompt -run “<< helloWorld.m”

exit 0

$ qsub math_job.pbs

Learn more about Mathematica at the Wolfram Website.