The odd-parameter pretzel knot strong quasipositivity conjecture

Let K=P(ϵ1p1,,ϵnpn)K=P(\epsilon_1p_1,\ldots,\epsilon_np_n) be the pretzel knot under consideration, where each pip_i is odd, and let d=ϵ1++ϵnd=\epsilon_1+\cdots+\epsilon_n.

Odd-parameter pretzel conjecture. The knot KK is strongly quasipositive if and only if either d=n|d|=n, or d=n2|d|=n-2 and, after possibly reordering so that ϵ1==ϵn1=+1\epsilon_1=\cdots=\epsilon_{n-1}=+1 and ϵn=1\epsilon_n=-1, one has pn<min{p1,,pn1}p_n<\min\{p_1,\ldots,p_{n-1}\}.

The source proves the asserted characterization in the cases d=n|d|=n and d=n2|d|=n-2, and proposes it for all odd parameters; the remaining cases are therefore open there.

Sources & referencesView supporting material

Primary source

Michel Boileau, Steven Boyer and Cameron McA. Gordon, “Branched covers of quasipositive links and L-spaces”, arXiv:1710.07658 (2019).

Progress summary

Never refreshed

Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.

Solutions 0

No solutions have been posted yet.