Data:K12n816/HOMFLYPT Polynomial

Failed to parse (syntax error): {\displaystyle -z^2 a^6-a^6+3 z^4 a^4+6 z^2 a^4+3 a^4-2 z^6 a^2-7 z^4 a^2-9 z^2 a^2-3 a^2+3 z^4+5 z^2+2-z^2}{a^2} $Failed^{-1} }