PS:
On 27 Jun., 07:59, Simon King <simon.k...@uni-jena.de> wrote:
> The existence proof for Seifert surfaces is constructive: Given a knot
> diagram (i.e., a generic orthogonal projection with over/
> undercrossings marked), it is straight forward to construct a Seifert
> surface.
>
> Much more complicated would it be to construct a Seifert surface of
> *minimal* genus.
That said: The algorithm that comes out of the existence proof is not
bad at all. As much as I remember, for alternating knot diagrams, it
yields a surface of minimal genus. And certainly the algorithm is very
*very* easy. So, the only problem is visualisation.
Cheers,
Simon
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