I use `crontab -e` without `sudo` to edit cron jobs and add the following line there - 

    20 22 23 10 * date "+%Y-%m-%d %H:%M:%S" >> ~/Documents/log.txt

then I check the log file and it doesn't contain the date and time. 

I tried to edit `crontab` as root, but it also doesn't update the file. What could be wrong here? Is there any way to see the log of cron jobs execution?

P.S. Update crontab created under root:

    0/5 * * * * /bin/date "+%Y-%m-%d %H:%M:%S" >> /tmp/log.txt
    0/5 * * * * echo >> /tmp/log2.txt

`log2.txt` is created now.