q 21 / 2 − 4 q 19 / 2 + 9 q 17 / 2 − 15 q 15 / 2 + 21 q 13 / 2 − 24 q 11 / 2 + 24 q 9 / 2 − 22 q 7 / 2 + 15 q 5 / 2 − 10 q 3 / 2 + 4 q − 1 q {\displaystyle q^{21/2}-4q^{19/2}+9q^{17/2}-15q^{15/2}+21q^{13/2}-24q^{11/2}+24q^{9/2}-22q^{7/2}+15q^{5/2}-10q^{3/2}+4{\sqrt {q}}-{\frac {1}{\sqrt {q}}}}
