Data:10 21/HOMFLYPT Polynomial

$z^4 a^8+3 z^2 a^8+a^8-z^6 a^6-4 z^4 a^6-5 z^2 a^6-3 a^6-z^6 a^4-3 z^4 a^4+2 a^4+z^4 a^2+3 z^2 a^2+a^2$