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