Fundamental Group of Sextics of Torus Type
نویسنده
چکیده
We show that the fundamental group of the complement of any irreducible tame torus sextics in P is isomorphic to Z2 ∗ Z3 except one class. The exceptional class has the configuration of the singularities {C3,9, 3A2} and the fundamental group is bigger than Z2 ∗ Z3. In fact, the Alexander polynomial is given by (t 2 − t + 1). For the proof, we first reduce the assertion to maximal curves and then we compute the fundamental groups for maximal tame torus curves.
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