Data:K12n869/HOMFLYPT Polynomial

[math]\displaystyle{ 2 z^6 a^{-4} -4 z^4 a^{-2} +7 z^4 a^{-4} -3 z^4 a^{-6} -7 z^2 a^{-2} +12 z^2 a^{-4} -6 z^2 a^{-6} +z^2 a^{-8} +2 z^2-3 a^{-2} +7 a^{-4} -5 a^{-6} + a^{-8} +1 }[/math]