a 18 z 4 − a 18 z 2 + 3 a 17 z 5 − 3 a 17 z 3 + a 17 z + 5 a 16 z 6 − 4 a 16 z 4 + a 16 z 2 + 7 a 15 z 7 − 9 a 15 z 5 + 5 a 15 z 3 + a 15 z + 7 a 14 z 8 − 11 a 14 z 6 + 8 a 14 z 4 − 3 a 14 z 2 + a 14 + 4 a 13 z 9 − 13 a 13 z 5 + 9 a 13 z 3 + a 13 z − a 13 z − 1 + a 12 z 10 + 10 a 12 z 8 − 35 a 12 z 6 + 39 a 12 z 4 − 22 a 12 z 2 + 3 a 12 + 7 a 11 z 9 − 19 a 11 z 7 + 20 a 11 z 5 − 24 a 11 z 3 + 16 a 11 z − 3 a 11 z − 1 + a 10 z 10 + 5 a 10 z 8 − 26 a 10 z 6 + 32 a 10 z 4 − 17 a 10 z 2 + 3 a 10 + 3 a 9 z 9 − 11 a 9 z 7 + 16 a 9 z 5 − 17 a 9 z 3 + 11 a 9 z − 2 a 9 z − 1 + 2 a 8 z 8 − 7 a 8 z 6 + 6 a 8 z 4 + a 7 z 7 − 5 a 7 z 5 + 8 a 7 z 3 − 4 a 7 z {\displaystyle a^{18}z^{4}-a^{18}z^{2}+3a^{17}z^{5}-3a^{17}z^{3}+a^{17}z+5a^{16}z^{6}-4a^{16}z^{4}+a^{16}z^{2}+7a^{15}z^{7}-9a^{15}z^{5}+5a^{15}z^{3}+a^{15}z+7a^{14}z^{8}-11a^{14}z^{6}+8a^{14}z^{4}-3a^{14}z^{2}+a^{14}+4a^{13}z^{9}-13a^{13}z^{5}+9a^{13}z^{3}+a^{13}z-a^{13}z^{-1}+a^{12}z^{10}+10a^{12}z^{8}-35a^{12}z^{6}+39a^{12}z^{4}-22a^{12}z^{2}+3a^{12}+7a^{11}z^{9}-19a^{11}z^{7}+20a^{11}z^{5}-24a^{11}z^{3}+16a^{11}z-3a^{11}z^{-1}+a^{10}z^{10}+5a^{10}z^{8}-26a^{10}z^{6}+32a^{10}z^{4}-17a^{10}z^{2}+3a^{10}+3a^{9}z^{9}-11a^{9}z^{7}+16a^{9}z^{5}-17a^{9}z^{3}+11a^{9}z-2a^{9}z^{-1}+2a^{8}z^{8}-7a^{8}z^{6}+6a^{8}z^{4}+a^{7}z^{7}-5a^{7}z^{5}+8a^{7}z^{3}-4a^{7}z}