− a 4 z 10 + a 6 z 8 − 8 a 4 z 8 + 2 a 2 z 8 + 7 a 6 z 6 − 25 a 4 z 6 + 12 a 2 z 6 − z 6 − a 8 z 4 + 16 a 6 z 4 − 39 a 4 z 4 + 25 a 2 z 4 − 4 z 4 − 2 a 8 z 2 + 15 a 6 z 2 − 30 a 4 z 2 + 23 a 2 z 2 − 5 z 2 − a 8 + 5 a 6 − 10 a 4 + 9 a 2 − 2 {\displaystyle -a^{4}z^{10}+a^{6}z^{8}-8a^{4}z^{8}+2a^{2}z^{8}+7a^{6}z^{6}-25a^{4}z^{6}+12a^{2}z^{6}-z^{6}-a^{8}z^{4}+16a^{6}z^{4}-39a^{4}z^{4}+25a^{2}z^{4}-4z^{4}-2a^{8}z^{2}+15a^{6}z^{2}-30a^{4}z^{2}+23a^{2}z^{2}-5z^{2}-a^{8}+5a^{6}-10a^{4}+9a^{2}-2}