Is it always 480? Is copy and paste cheating?

480 is conveniently 30 * 16, so it's M * 10 (can most people count that high?),  then Ctrl-A, Ctrl-X, Ctrl-V, Ctrl-V, Ctrl-V

After that, it's

Ctrl-A, Ctrl-X, Ctrl-V, Ctrl-V

repeated 5 times. Should be 480 repeats.

Stewart