− q 7 / 2 + 4 q 5 / 2 − 9 q 3 / 2 + 14 q − 19 q + 20 q 3 / 2 − 21 q 5 / 2 + 17 q 7 / 2 − 12 q 9 / 2 + 7 q 11 / 2 − 3 q 13 / 2 + 1 q 15 / 2 {\displaystyle -q^{7/2}+4q^{5/2}-9q^{3/2}+14{\sqrt {q}}-{\frac {19}{\sqrt {q}}}+{\frac {20}{q^{3/2}}}-{\frac {21}{q^{5/2}}}+{\frac {17}{q^{7/2}}}-{\frac {12}{q^{9/2}}}+{\frac {7}{q^{11/2}}}-{\frac {3}{q^{13/2}}}+{\frac {1}{q^{15/2}}}}