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**Danneedshelp** Q) Prove or disprove: there exist infinitely many composite numbers of the form $\displaystyle 2^{n}-1$, where $\displaystyle n$ is any positive integer.

I am not sure how to approach this. I beleive that the statement is true, but I am not sure how to approach this proof. My first thought is to do a proof by contradiction by assuming I can list all such composite number. However, I cannot find a way to arrive at a contradiction.

Some direction would be appreciated.