Permanent mouse speed change in 16.04 [duplicate]
The easiest way would be adding the command to Startup application, first we'll wrap the command with bash script.
touch speedmouse.sh
Then, append your command:
echo "xinput set-prop 13 276 0.7" >> speedmouse.sh
Press Alt + F2, type gnome-session-properties to launch startup application. Press Add to create new startup:
You should all set now.