Greg Egan, Shrinking the Superpermutations: plus.google.com/11308655330045
Greg suggests a formula for their length, and constructs superpermutations of length only one more than the formula.

They should not be confused with superpatterns (en.wikipedia.org/wiki/Superpat) which contain all permutations of a given length for a different definition of containment, and are a lot shorter, but also somewhat mysterious in length.

@11011110
Since I am now also on Maston, I'll more or less repeat what I just replied to Greg's post on Google plus.
I wonder if it makes more sense to consider a circular string, ie the first character is considered adjacent to the last and vice versa. That seems more symmetrical to me.
Gerard

@GerardWestendorp For the graph drawing applications I have been using superpatterns for, I needed linear sequences not cyclic sequences. But of course that was superpatterns not superpermutations.

A Mastodon instance for maths people. The kind of people who make $\pi z^2 \times a$ jokes.

Use $ and $ for inline LaTeX, and $ and $ for display mode.