− a 4 z 10 + 2 a 6 z 8 − 7 a 4 z 8 + a 2 z 8 − a 8 z 6 + 12 a 6 z 6 − 19 a 4 z 6 + 5 a 2 z 6 − 5 a 8 z 4 + 26 a 6 z 4 − 24 a 4 z 4 + 8 a 2 z 4 − 8 a 8 z 2 + 23 a 6 z 2 − 12 a 4 z 2 + 4 a 2 z 2 − 4 a 8 + 6 a 6 − a 4 {\displaystyle -a^{4}z^{10}+2a^{6}z^{8}-7a^{4}z^{8}+a^{2}z^{8}-a^{8}z^{6}+12a^{6}z^{6}-19a^{4}z^{6}+5a^{2}z^{6}-5a^{8}z^{4}+26a^{6}z^{4}-24a^{4}z^{4}+8a^{2}z^{4}-8a^{8}z^{2}+23a^{6}z^{2}-12a^{4}z^{2}+4a^{2}z^{2}-4a^{8}+6a^{6}-a^{4}}