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