− z 2 a 14 + a 14 + z 4 a 12 − 4 z 2 a 12 − 4 a 12 + 5 z 4 a 10 + 7 z 2 a 10 + 3 a 10 + 3 z 4 a 8 + z 2 a 8 − a 8 + z 6 a 6 + 6 z 4 a 6 + 6 z 2 a 6 + 2 a 6 {\displaystyle -z^{2}a^{14}+a^{14}+z^{4}a^{12}-4z^{2}a^{12}-4a^{12}+5z^{4}a^{10}+7z^{2}a^{10}+3a^{10}+3z^{4}a^{8}+z^{2}a^{8}-a^{8}+z^{6}a^{6}+6z^{4}a^{6}+6z^{2}a^{6}+2a^{6}}