Data:K12n885/HOMFLYPT Polynomial

Failed to parse (syntax error): {\displaystyle -z^6}{a^2}- $Failed^{-1} -z^6+a^2 z^4-z^4}{a^2}+ $Failed^{-1} +z^4}{a^4}- $Failed^{-1} -2 a^2 z^2-z^2}{a^2}+ $Failed^{-1} +2 z^2+a^4-2 a^2+2}