Data:L10a134/HOMFLYPT Polynomial

$a^6 z^{-2} +a^6-3 a^4 z^2-2 a^4 z^{-2} -4 a^4+3 a^2 z^4+z^4 a^{-2} +6 a^2 z^2+a^2 z^{-2} +z^2 a^{-2} +4 a^2+ a^{-2} -z^6-3 z^4-5 z^2-2$