Skip to main content
9 events
when toggle format what by license comment
Feb 3, 2022 at 13:26 vote accept Sam Hopkins
Jan 31, 2022 at 23:21 comment added Sam Hopkins @RichardStanley: Thank you for the reference!
Jan 31, 2022 at 23:16 comment added Richard Stanley @SamHopkins: this is essentially what appears in Section 5.3 of Combinatorics: The Rota Way by Kung, Rota, and Yan.
Jan 31, 2022 at 22:51 comment added Sam Hopkins This does make me wonder if there is a way to understand the basic Pólya counting results in terms of the quotient of the ordered partition lattice by $G$, and maybe Möbius inversion on this poset...
Jan 31, 2022 at 18:28 comment added Nate @darijgrinberg Oh yea, good point.
Jan 31, 2022 at 18:24 comment added darij grinberg @Nate I don't think that expansion has integer coefficients always. $a_j$ is not necessarily a multiple of $j!$. You get some kind of non-freeness problems with your action.
Jan 31, 2022 at 18:22 comment added Nate Ahh yea I realized this ordering issue when I was at lunch just now and was going to comment but you beat me to it. The equivalence relation formulation I mentioned instead gives you the coefficients for expanding it in terms of permutation polynomials $j! \binom{x}{j}$.
S Jan 31, 2022 at 17:56 history answered Sam Hopkins CC BY-SA 4.0
S Jan 31, 2022 at 17:56 history made wiki Post Made Community Wiki by Sam Hopkins