/usr/bin/lastb

Usage:
 lastb [options] [<username>...] [<tty>...]

Show a listing of last logged in users.

Options:
 -<number>            how many lines to show
 -a, --hostlast       display hostnames in the last column
 -d, --dns            translate the IP number back into a hostname
 -f, --file <file>    use a specific file instead of /var/log/btmp
 -F, --fulltimes      print full login and logout times and dates
 -i, --ip             display IP numbers in numbers-and-dots notation
 -n, --limit <number> how many lines to show
 -p, --present <time> display who were present at the specified time
 -R, --nohostname     don't display the hostname field
 -s, --since <time>   display the lines since the specified time
 -t, --until <time>   display the lines until the specified time
 -T, --tab-separated  use tabs as delimiters
     --time-format <format>  show timestamps in the specified <format>:
                               notime|short|full|iso
 -w, --fullnames      display full user and domain names
 -x, --system         display system shutdown entries and run level changes

 -h, --help           display this help
 -V, --version        display version

For more details see last(1).