MathDB

17

Part of 2017 Harvard-MIT Mathematics Tournament

Problems(1)

2017 Guts #17: Maximal number of subsequences

Source:

2/21/2017
Sean is a biologist, and is looking at a strng of length 6666 composed of the letters AA, TT, CC, GG. A substring of a string is a contiguous sequence of letters in the string. For example, the string AGTCAGTC has 1010 substrings: AA, GG, TT, CC, AGAG, GTGT, TCTC, AGTAGT, GTCGTC, AGTCAGTC. What is the maximum number of distinct substrings of the string Sean is looking at?
combinatorics