q 21 / 2 − 2 q 19 / 2 + 4 q 17 / 2 − 6 q 15 / 2 + 8 q 13 / 2 − 10 q 11 / 2 + 10 q 9 / 2 − 9 q 7 / 2 + 6 q 5 / 2 − 5 q 3 / 2 + 2 q − 1 q {\displaystyle q^{21/2}-2q^{19/2}+4q^{17/2}-6q^{15/2}+8q^{13/2}-10q^{11/2}+10q^{9/2}-9q^{7/2}+6q^{5/2}-5q^{3/2}+2{\sqrt {q}}-{\frac {1}{\sqrt {q}}}}
