q 13 − 2 q 12 + 4 q 11 − 7 q 10 + 8 q 9 − 9 q 8 + 8 q 7 − 7 q 6 + 5 q 5 − 2 q 4 + 2 q 3 {\displaystyle q^{13}-2q^{12}+4q^{11}-7q^{10}+8q^{9}-9q^{8}+8q^{7}-7q^{6}+5q^{5}-2q^{4}+2q^{3}}
