− q 13 / 2 + 4 q 11 / 2 − 9 q 9 / 2 + 13 q 7 / 2 − 17 q 5 / 2 + 18 q 3 / 2 − 17 q + 13 q − 9 q 3 / 2 + 4 q 5 / 2 − 1 q 7 / 2 {\displaystyle -q^{13/2}+4q^{11/2}-9q^{9/2}+13q^{7/2}-17q^{5/2}+18q^{3/2}-17{\sqrt {q}}+{\frac {13}{\sqrt {q}}}-{\frac {9}{q^{3/2}}}+{\frac {4}{q^{5/2}}}-{\frac {1}{q^{7/2}}}}
