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Yash Agarwal

2. There are 6 sequences possible for the number of A’s always being greater than or equal to the number of B’s. One thing we do know for certain is that we have to start with an A. So, we can consider this as a 3 letter sequence with the number of A’s always being at least 1 less than the number of B’s. The 6 sequences are:

ABB

BAB

BAA

AAA

ABA

AAB

I do not think we can generalize to n since there is no pattern or sequence. If the length is 2, the number of sequences is 2. If 3, then 3. If 4, then 6. If 5, then 10. …

**This response was written by Yash Agarwal**