q 21 / 2 − 4 q 19 / 2 + 9 q 17 / 2 − 15 q 15 / 2 + 19 q 13 / 2 − 23 q 11 / 2 + 22 q 9 / 2 − 19 q 7 / 2 + 14 q 5 / 2 − 8 q 3 / 2 + 3 q − 1 q {\displaystyle q^{21/2}-4q^{19/2}+9q^{17/2}-15q^{15/2}+19q^{13/2}-23q^{11/2}+22q^{9/2}-19q^{7/2}+14q^{5/2}-8q^{3/2}+3{\sqrt {q}}-{\frac {1}{\sqrt {q}}}}
