Sorry you wanted the cron info:

0 0 * * 7 sync ; echo 3 | /sbin/reboot


This reboots at midnight every Sunday..

#       The time and date fields are:
#
#             field          allowed values
#              -----          --------------
#              minute         0-59
#              hour           0-23
#              day of month   1-31
#              month          1-12 (or names, see below)
#              day of week    0-7 (0 or 7 is Sun, or use names)


From: w6reb <w6reb@hammradio.us>
Reply-To: w6reb <w6reb@hammradio.us>
Date: Wed, 14 Dec 2011 11:03:02 -1000
To: "app_rpt-users@ohnosec.org" <app_rpt-users@ohnosec.org>
Subject: [App_rpt-users] Reboot

             What would be the proper syntax to reboot computer once a week in the middle of the night?
           Know how to write schedule or contab just need the right syntax for shutdown -r now as though
           I'm doing it from the root@