Puzzles
21 December
Permanent link to this puzzle: mscroggs.co.uk/puzzles/advent2023/21
There are 6 two-digit numbers whose digits are all 1, 2, or 3 and whose second digit onwards
are all less than or equal to the previous digit:
- 33
- 22
- 31
- 21
- 11
- 32
How many 20-digit numbers are there whose digits are all 1, 2, or 3 and whose second digit onwards
are all less than or equal to the previous digit?