A friend of mine was writing a paper arguing against allowing patents for genetic sequences. In one case, a company patented a 15-gene sequence. He asked mt how many 100-gene genomes contain this sequence.
Now a gene can be one of 4 possibilities: A,T,C,G. So when i attempted to compute this counting problem, I thought for the specific 15-gene sequence, there were 86 possible starting points, and for any of the 86 genes not in the sequence there were 4 possible outcomes, so I came up with the computation:
Why is this computation wrong? explain and/or show your work