FAQ for Tom's Snake-in-the-Box page

What is the Snake-in-the-Box problem?
It's problem of finding the longest possible path on edges of an n-dimensional hypercube that meets a certain constraint. Wikipedia has a good introduction to the problem (and the related Coil-in-the-Box problem).

The problem has been solved in up to 8 dimensions, where instances of the longest possible path ('snake') have been constructed and also shown to be maximal. In 9 dimensions and above, there are known lower bounds (lengths of constructed snakes) and upper bounds (theoretical maxiumum limits on snake length). This site's Snake-in-the-Box page catalogs lower bounds: examples of longest-known snakes/coils in dimensions 1‑13.

What's the point?
The Snake-in-the-Box problem arose in the study of error-correcting and ‑detecting codes and has applications in that area. It has also become a benchmark problem for testing algorithms that search enormous solution spaces.

How are vertices and transitions numbered?
Please see my 2025 paper.

Do the numbers in your transition sequences match the conventions used in the references cited?
Not always. Dimension numbers here are zero‑based hexadecimal digits. Coils (even symmetric coils) are spelled out in full and include the edge that that returns to the initial vertex.

Are these really the current best results?
I can't be sure. I welcome reports of new records and will update my page accordingly.

Where can I see an animated video of a projection of a 6‑dimensional snake?
Glad you asked! Please see https://youtu.be/5wPoS4Cj_rU
For best results, select 1080p (HD) quality under Settings.