q 23 / 2 − 4 q 21 / 2 + 9 q 19 / 2 − 13 q 17 / 2 + 17 q 15 / 2 − 18 q 13 / 2 + 17 q 11 / 2 − 15 q 9 / 2 + 9 q 7 / 2 − 6 q 5 / 2 + 2 q 3 / 2 − q {\displaystyle q^{23/2}-4q^{21/2}+9q^{19/2}-13q^{17/2}+17q^{15/2}-18q^{13/2}+17q^{11/2}-15q^{9/2}+9q^{7/2}-6q^{5/2}+2q^{3/2}-{\sqrt {q}}}