Imagine a 2-dimensional vector space in $\mathbb{Z} /2 \mathbb{Z}$. The only possible basis' are $ \left(\begin{array}{c} 1\\ 0 \end{array}\right), \left(\begin{array}{c} 0\\ 1 \end{array}\right); \left(\begin{array}{c} 1\\ 1 \end{array}\right), \left(\begin{array}{c} 0\\ 1 \end{array}\right);\left(\begin{array}{c} 1\\ 0 \end{array}\right), \left(\begin{array}{c} 1\\ 1 \end{array}\right)$
This means for n = 2 would 3 be the correct answer. For n = 1 the answer is 1.
What is the correct answer for a variable n?