The strong rearrangement bijection conjecture for generalized factor order

Let P\mathbb{P}^* be the set of finite words over the positive integers, let F(u)\mathcal{F}(u) denote the set of words containing uu as a factor in generalized factor order, and let uvu\backsim v denote Wilf equivalence. A bijection is weight-preserving when it preserves the weight of every word, and a word is a rearrangement of another when it has the same multiset of letters. Strong rearrangement bijection conjecture. If uvu\backsim v, then there is a weight-preserving bijection

f:PPf:\mathbb{P}^*\longrightarrow\mathbb{P}^*

such that for every wPw\in\mathbb{P}^*, f(w)f(w) is a rearrangement of ww and

wF(u)    f(w)F(v).w\in\mathcal{F}(u)\iff f(w)\in\mathcal{F}(v).

This would strengthen the weak rearrangement conjecture by realizing Wilf equivalence through a letter-rearranging bijection, and is left open in the paper.

Sources & referencesView supporting material

Primary source

Thomas Langley, Jeffrey Liese and Jeffrey Remmel, “Generating functions for Wilf equivalence under generalized factor order”, arXiv:1005.4372 (2010).

Progress summary

Never refreshed

Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.

Solutions 0

No solutions have been posted yet.