As long as you have more samples than you need in the table you can squeeze the time base.
A sine wave is very simple mathematically as y=h*sin(x). X varies from 0 to 360 degrees and then the wave repeats, so no need to work out any more. The h for the arduino is 255 as there is no need for a bigger number. The only real variable is the step in the degrees that you want to hold and with 5 degree difference between points we get a table of 72 data points. In 10 seconds that makes it 7.2 changes to the led in 1 second, easily done.
If you only want 5 seconds, then you just take every other value in the table or have more transitions per second.