Just remember how to derive.
1. take out FINOQVW from the 26 alphabets.
2. reverse the order. ZYX…......
3. take alternate alphabets.
ZXTRMKHECAYUSPLJGDB.
4. follow these exceptions:
9 to 10, skip 1 alphabet
99 to 100, skip 8 alphabets
999 to 1000, same alphabet
Our fellow mod's name's on it!