In https://scholar.harvard.edu/files/schwartz/files/12-bec.pdf, the article says "With Bose-Einstein statistics, we determined that using the grand canonical ensemble the expected number of particles in a state i is"
$$\langle{n}_{i}\rangle=\frac {1}{e^{\beta(\varepsilon _{i}-\mu )}-1}$$
And it goes on and derive the relationship between the total number of particles and the number of particles in the ground state.
$$N=\sum_{n_x,n_y,n_z=0}\frac{1}{e^{\beta\varepsilon_{1}(n_x^2+n_y^2+n_z^2)}\left(\frac{1}{\langle{n_0}\rangle}+1\right)-1}$$
However, as I understand, the equation for the expected number of particles in a state i is
$$\langle{n}_{i}\rangle=\frac {g_i}{e^{\beta(\varepsilon _{i}-\mu )}-1}$$ where $g_i$ is the degeneracy of energy level $i$. My question is why can I assume $g_i=1$ in this case since wouldn't that affect the answer?