Data:L9a21/HOMFLYPT Polynomial

$-a^3 z^5-3 a^3 z^3-2 a^3 z+a^3 z^{-1} +a z^7+5 a z^5-z^5 a^{-1} +8 a z^3-3 z^3 a^{-1} +3 a z-2 z a^{-1} -a z^{-1}$