### The function crossing_number run too slowly

In graph theory, the crossing number *cr(G)* of a graph *G* is the lowest number of edge crossings of a plane drawing of the graph *G*. In general, determining the crossing number of a graph is hard. However, for graphs with a small number of vertices and a small number of edges, some efficient procedures exist to compute them.

The *exact* and **non-heuristic** programs that I know of are the following:

- sagemath
- web crossing number (http://crossings.uos.de/) #Recent login is not available, the website may be under maintenance, or maybe not to provide services in the future)
- OGDF(https://ogdf.uos.de/)

I see an example of mathoverflow from 10 years ago, which is to compute the cross number of the Grötzsch graph.

Jamie J. Taylor says in the answer that OGDF can be used. But we don't see the corresponding code. I know that Sagemath has the crossing_number, Unfortunately, it may be too ~~slow~~slow.

```
G = graphs.GrotzschGraph()
G.crossing_number()
```

It took me about 12 hours, and I haven't gotten a result yet. Perhaps there is some way to improve it?