− a 4 z 10 + 2 a 6 z 8 − 8 a 4 z 8 + a 2 z 8 − a 8 z 6 + 13 a 6 z 6 − 26 a 4 z 6 + 6 a 2 z 6 − 5 a 8 z 4 + 31 a 6 z 4 − 42 a 4 z 4 + 13 a 2 z 4 − 8 a 8 z 2 + 31 a 6 z 2 − 32 a 4 z 2 + 12 a 2 z 2 − 4 a 8 + 10 a 6 − 9 a 4 + 4 a 2 {\displaystyle -a^{4}z^{10}+2a^{6}z^{8}-8a^{4}z^{8}+a^{2}z^{8}-a^{8}z^{6}+13a^{6}z^{6}-26a^{4}z^{6}+6a^{2}z^{6}-5a^{8}z^{4}+31a^{6}z^{4}-42a^{4}z^{4}+13a^{2}z^{4}-8a^{8}z^{2}+31a^{6}z^{2}-32a^{4}z^{2}+12a^{2}z^{2}-4a^{8}+10a^{6}-9a^{4}+4a^{2}}
