Greg Egan, Shrinking the Superpermutations: https://plus.google.com/113086553300459368002/posts/4VB8Xi3i2Gt
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 (https://en.wikipedia.org/wiki/Superpattern) 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.
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.
@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.
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