q 12 − 5 q 11 + 10 q 10 − 15 q 9 + 19 q 8 − 21 q 7 + 20 q 6 − 16 q 5 + 11 q 4 − 5 q 3 + 2 q 2 {\displaystyle q^{12}-5q^{11}+10q^{10}-15q^{9}+19q^{8}-21q^{7}+20q^{6}-16q^{5}+11q^{4}-5q^{3}+2q^{2}}
