- #1

- 178

- 0

I am asked to find a recurrence relation for the number of n letter sequences composed of A, B, C where every A that is not in the last position is followed by a B.

So, would this be:

A| (we have A(n-2) sequences) + 0 if A is in the last position

B| we have A(n-1)

C| we have A(n-1)

So does this mean that A(n) = A(n-1) + 2*A(n-1)? But this seems simplistic ....

Thanks.