Unknotting Numbers of Diagrams of a given Nontrivial Knot Are Unbounded
نویسنده
چکیده
We show that for any nontrivial knot K and any natural number n there is a diagram D of K such that the unknotting number of D is greater than or equal to n. It is well known that twice the unknotting number of K is less than or equal to the crossing number of K minus one. We show that the equality holds only when K is a (2, p)-torus knot.
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تاریخ انتشار 2008