∑

**n**=

**1**to ∞ (3

^{n}/(2

^{n}-1))

the expression is above and I have to use the DIRECT COMPARISON test to determine the convergence or divergence of the series.

I know that this expression diverges, and I also know that I have to find some sequence that is smaller than the one given and prove the divergence of that sequence to prove this sequence, but I don't know which one to use.

Which sequence do I have to compare that with?