q 21 / 2 − 3 q 19 / 2 + 6 q 17 / 2 − 11 q 15 / 2 + 15 q 13 / 2 − 17 q 11 / 2 + 17 q 9 / 2 − 16 q 7 / 2 + 11 q 5 / 2 − 7 q 3 / 2 + 3 q − 1 q {\displaystyle q^{21/2}-3q^{19/2}+6q^{17/2}-11q^{15/2}+15q^{13/2}-17q^{11/2}+17q^{9/2}-16q^{7/2}+11q^{5/2}-7q^{3/2}+3{\sqrt {q}}-{\frac {1}{\sqrt {q}}}}
