Given sequence of numbers from 0 to X, where
0 = 000000,
...,
999_999 = 999999,
1_000_000 = 00000A,
1_000_001 = 00001A,
...,
_ = 99999A,
_ = 00000B,
...,
_ = 00000Z,
_ = 00001Z,
...,
_ = 99999Z,
_ = 0000AZ,
...,
_ = 9ZZZZZ,
_ = AZZZZZ,
...,
X - 1 = YZZZZZ,
X = ZZZZZZ.
Write a function to encode N (from 0 to X) in this format.