Lin's symmetry conjecture for ascents of restricted inversion sequences

From papers

For n1n\geq 1, let In(,,>)\mathbf{I}_n(\geq,\neq,>) and In(>,,)\mathbf{I}_n(>,\neq,\geq) be the two classes of inversion sequences avoiding the indicated relation triples. For an inversion sequence ee, let asc(e)\operatorname{asc}(e) be its number of ascents. Lin's symmetry conjecture.

eIn(,,>)tasc(e)=eIn(>,,)tn1asc(e).\sum_{e\in\mathbf{I}_n(\geq,\neq,>)}t^{\operatorname{asc}(e)}=\sum_{e\in\mathbf{I}_n(>,\neq,\geq)}t^{n-1-\operatorname{asc}(e)}.

This predicts a palindromic correspondence between ascent distributions in the two inversion-sequence classes. The paper states that Lin's earlier bijection does not prove this symmetry, and no resolution is supplied in the provided text.

Progress summary

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

Sources & referencesView supporting material

Primary source

Joanna N. Chen and Zhicong Lin, “Combinatorics of the symmetries of ascents in restricted inversion sequences”, arXiv:2112.04115 (2021).

Solutions 0

No solutions have been posted yet.