Bounded comparison for odd-crossing and crossing numbers
Establish whether there is a universal constant c > 0 such that the odd-crossing number of every graph is at most c times its crossing number.
References
Similar problem for the odd-crossing number, is there a constant $c>0$ such that $(G)\le c(G)$ for every graph $G$?
— Generalizations of the Crossing Lemma
(2509.14074 - Toth, 17 Sep 2025) in Section 5, Open problems, item 5