Challenge 131: Beautiful Numbers
Can you find how many 3 digit beautiful numbers there are?
If you add the 3-digit integer 123 to its “reverse”, 321, you get 444 –another 3-digit integer, but using only one number – in this case, 4.
We will describe an integer with this property as a beautiful number.
How many 3-digit beautiful numbers are there? How many with 4 digits?
Can you generalise?