q 2 − q + 2 − 2 q + 1 q 2 − 1 q 3 + 1 q 4 {\displaystyle q^{2}-q+2-{\frac {2}{q}}+{\frac {1}{q^{2}}}-{\frac {1}{q^{3}}}+{\frac {1}{q^{4}}}}
