z 7 a + z 7 a 3 + 4 z 6 a 2 + 2 z 6 a 4 + 2 z 6 + a z 5 − z 5 a + 2 z 5 a 5 − 12 z 4 a 2 − 3 z 4 a 4 + 2 z 4 a 6 − 7 z 4 − 3 a z 3 − 3 z 3 a − 2 z 3 a 3 − z 3 a 5 + z 3 a 7 + 12 z 2 a 2 + 4 z 2 a 4 − 2 z 2 a 6 + 6 z 2 + a z + 2 z a + 2 z a 3 − z a 7 − 4 a 2 − 2 a 4 − 1 {\displaystyle {\frac {z^{7}}{a}}+{\frac {z^{7}}{a^{3}}}+{\frac {4z^{6}}{a^{2}}}+{\frac {2z^{6}}{a^{4}}}+2z^{6}+az^{5}-{\frac {z^{5}}{a}}+{\frac {2z^{5}}{a^{5}}}-{\frac {12z^{4}}{a^{2}}}-{\frac {3z^{4}}{a^{4}}}+{\frac {2z^{4}}{a^{6}}}-7z^{4}-3az^{3}-{\frac {3z^{3}}{a}}-{\frac {2z^{3}}{a^{3}}}-{\frac {z^{3}}{a^{5}}}+{\frac {z^{3}}{a^{7}}}+{\frac {12z^{2}}{a^{2}}}+{\frac {4z^{2}}{a^{4}}}-{\frac {2z^{2}}{a^{6}}}+6z^{2}+az+{\frac {2z}{a}}+{\frac {2z}{a^{3}}}-{\frac {z}{a^{7}}}-{\frac {4}{a^{2}}}-{\frac {2}{a^{4}}}-1}
