− z 2 a 14 + a 14 + z 4 a 12 − 4 z 2 a 12 − 4 a 12 + 4 z 4 a 10 + 4 z 2 a 10 + a 10 + z 6 a 8 + 8 z 4 a 8 + 9 z 2 a 8 + 3 a 8 + z 6 a 6 + 5 z 4 a 6 + 3 z 2 a 6 {\displaystyle -z^{2}a^{14}+a^{14}+z^{4}a^{12}-4z^{2}a^{12}-4a^{12}+4z^{4}a^{10}+4z^{2}a^{10}+a^{10}+z^{6}a^{8}+8z^{4}a^{8}+9z^{2}a^{8}+3a^{8}+z^{6}a^{6}+5z^{4}a^{6}+3z^{2}a^{6}}