I have 13 lines of powered rails, each 16 blocks long. If I number the rails from left to right, I need to activate them in this order: 1, 3 2, 5 4 3, 7 6 5 4, 9 8 7 6 5, 11 10 9 8 7 6, 13 12 11 10 9 8 7 (see the second photo).
There should be a 2 tick delay between activations (like 2 observers).
The lines are long, so it would be good to activate them from below (you can replace the grass blocks under the rails)
by Additional_Twist_464