An alphabet with two letters A and B has rules for creating words:

1. Any A must be part of a string containing an even number of A's.
2. Any B must be part of a string of containing an odd number of B's.

For example two six letter words could be BBBAAB and AAAAAA but ABABBB would not be valid.

How many valid 15 letter words are there?

Check these positive words that start with S but there are only two that have 15 letters. However, there are many with 5 and 6 letters.

Posted by Danila Kaliko on 2023-04-13 15:29:59