cron does not have that ability, but you could use a conditional test on a files existence before it runs your comnand and then use ‘like 9’ “at” commands to touch the conditional file on the appropriate days
You could do that but it is incredibly ugly, the table will be in /var/spool/cron/crontabs/(user)
if you do that from bash you will need to reload cron.
If the file doesn’t exist the cron job will fail with an email containing the stderr and stdout of the job being sent to the email of the owner of the cron job. Perhaps more elegantly :-
[[ -f (your file) ]] && (do your job)
from a shell
man at
the ‘at’ job can indeed delete the file if it exists when it runs, and you can set the at trigger to be anytime in the future. That way if the file is not there then when the cron job runs, there is no stderr or stdout generated.