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