− q 25 + q 23 − 2 q 21 + q 19 + q 13 − q 11 + 2 q 9 + q 5 {\displaystyle -q^{25}+q^{23}-2q^{21}+q^{19}+q^{13}-q^{11}+2q^{9}+q^{5}}
