Music on the planet Alpha Lyra IV consists of only two notes, called A and B. Also, songs never include three consecutive repetitions of any sequence nor does BB ever occur. A sequence of notes can have 1 or more notes in it.
What is the longest song on Alpha Lyra IV?
(In reply to question about answr
Under the provisions governing to the problem under reference, three consecutive occurence of the letter "A" is deemed invalid.
However, the the maximum number of consecutive occurence of the letter "A" in the string "AABABAABABAABAAB" is two, which is fully in conformity with the conditions of the problem.