Enable the numeric keypad by default.
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# Numeric keypad

With the Num Lock key you can manually switch on or off the numeric keypad on your keyboard. Also, computers' BIOS settings often include an option to decide if the computer should be started with the numeric keypad enabled. Otherwise, this is a way to configure it:

Install the numlockx package.

Open Startup Applications and add a startup program with the command: numlockx on

The second step may be redundant on your computer, so try without it first.