− q + 4 q − 9 q 3 / 2 + 13 q 5 / 2 − 18 q 7 / 2 + 20 q 9 / 2 − 20 q 11 / 2 + 16 q 13 / 2 − 12 q 15 / 2 + 7 q 17 / 2 − 3 q 19 / 2 + 1 q 21 / 2 {\displaystyle -{\sqrt {q}}+{\frac {4}{\sqrt {q}}}-{\frac {9}{q^{3/2}}}+{\frac {13}{q^{5/2}}}-{\frac {18}{q^{7/2}}}+{\frac {20}{q^{9/2}}}-{\frac {20}{q^{11/2}}}+{\frac {16}{q^{13/2}}}-{\frac {12}{q^{15/2}}}+{\frac {7}{q^{17/2}}}-{\frac {3}{q^{19/2}}}+{\frac {1}{q^{21/2}}}}
