− a 4 z 10 + a 6 z 8 − 7 a 4 z 8 + 2 a 2 z 8 + 5 a 6 z 6 − 19 a 4 z 6 + 11 a 2 z 6 − z 6 + 8 a 6 z 4 − 25 a 4 z 4 + 20 a 2 z 4 − 4 z 4 + 5 a 6 z 2 − 15 a 4 z 2 + 14 a 2 z 2 − 4 z 2 + a 6 − 3 a 4 + 3 a 2 {\displaystyle -a^{4}z^{10}+a^{6}z^{8}-7a^{4}z^{8}+2a^{2}z^{8}+5a^{6}z^{6}-19a^{4}z^{6}+11a^{2}z^{6}-z^{6}+8a^{6}z^{4}-25a^{4}z^{4}+20a^{2}z^{4}-4z^{4}+5a^{6}z^{2}-15a^{4}z^{2}+14a^{2}z^{2}-4z^{2}+a^{6}-3a^{4}+3a^{2}}