Data:K12n833/HOMFLYPT Polynomial

Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 2 a^2 z^6+z^6-2 a^4 z^4+8 a^2 z^4-z^4}{a^2}+ $Failed^{-1} +2 z^4-5 a^4 z^2+12 a^2 z^2-2 z^2}{a^2}- $Failed^{-1} -4 a^4+7 a^2-1}{a^2}- $Failed^{-1} -1}