More keystrokes, but fewer lines of terminal output. Why have 5 lines of output when I don't want any?

  ktm5j@kurma /pool/share/pkgs $ ed ~/.ssh/known_hosts 
  130923
  398d
  wq
  130755

Sed just quietly does what I want. Like I said, just another way to skin a cat, do whatever works for you.

You can put the sed version in a cron job