[ x^4 + 1, \
x^4 + 2*x^2 + 2, \
x^4 + 2*x^2 - 1, \
x^4 - 4*x^2 + 2, \
x^4 - 2, \
x^4 + 4*x^2 + 2, \
x^4 + 2 ]