Conjecture 1: Maximum($G_n$)=$\frac{n+2}{2}$ in case $n$ is even and Maximum($G_n$)=$\frac{n+1}{2}$ in case $n$ is odd.
Conjecture 2: a) For $n$ even the number of perfect tuples $(w,v)$ with $w=(n+2)/2$ is equal to $\frac{3^{n/2-1}+1}{2}$ when we identify two tuples $(w,v_1)$ and $(w,v_2)$ when $v_1$ is a cyclic shift of $v_2$.
b) For $n$ odd the number of perfect tuples $(w,v)$ with $w=(n+1)/2$ is equal to $n-1$ when we identify two tuples $(w,v_1)$ and $(w,v_2)$ when $v_1$ is a cyclic shift of $v_2$.