Cerbai–Claesson–Ferrari bijection conjecture for 201-avoiding ascent sequences

About 4 years old · traced to

Let An(201)A_n(201) be the set of ascent sequences of length nn avoiding the pattern 201201, and let SnS_n be the set of permutations of length nn. A permutation is 312312-machine sortable if it can be sorted using two series-connected stacks whose first stack avoids 312312 when read from top to bottom and whose second stack is increasing.

Cerbai–Claesson–Ferrari conjecture. For every n≥0n\geq 0, there is a bijection between An(201)A_n(201) and the permutations in SnS_n that are 312312-machine sortable.

The conjecture is supported by data reported by Cerbai, Claesson, and Ferrari, but the source gives no proof.

References

Primary source

Eric S. Egge, “Pattern-Avoiding Fishburn Permutations and Ascent Sequences”, arXiv:2208.01484 (2022).

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.