Each round wraps the current number in a small mirror: reverse the digits of i on the left, i itself on the right — and, when required, keeps searching until the result is prime.
9552025559→9552025559
Created by Inder J. Taneja
The script itself never stops (it's a while True loop) — this caps it at a fixed number of lines instead.
Each round searches i = 1, 2, 3 … (skipping any i that contains an excluded digit) until reverse(i) + START + i is prime — exactly what the script does.
Every prime between a and b that reads the same forwards and backwards — generated directly from mirrored halves, so even wide ranges stay fast.