Unknotting number and knot diagram
نویسندگان
چکیده
TImis note is a continuation of [Nl], Wbere we have discusged tbe unknotting number of knots With rspect tía knot diagrams. Wc wilI show that for every minimum-crossing knot-diagram among ah unknotting-number-one two-bridge knot there exist crossings whose exchangeyields tIme trivial knot, ib tbe tbird Tait conjecture is true.
منابع مشابه
Unknotting Numbers of Diagrams of a given Nontrivial Knot Are Unbounded
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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