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Nov 22 at 0:03 history bumped CommunityBot This question has answers that may be good or bad; the system has marked it active so that they can be reviewed.
Sep 17 at 19:21 comment added Tom Copeland Re the third involution, see tree diagrams on p. 9 of "Tree hook length formulae, Feynman rules and B-series by Jones and Yeats (arxiv.org/abs/1412.6053), oeis.org/A355201, and $[A^{(-1)} ]$ in my extended answer below.
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Nov 3, 2023 at 0:12 comment added Tom Copeland An example of this pair of Laurent series are at the top of p. 24 of "Löwner equations and dispersionless hierarchies" by Takashi Takebe, Lee-Peng Teo, and Anton Zabrodin (arxiv.org/abs/math/0605161). See also eqn. 4.1 on p. 8.
Jul 31, 2023 at 17:34 comment added Tom Copeland @SamHopkins, not directly. I've seen the paper before. It seems to deal with only purely triangular Riordan matrices--not an infinite set of indeterminates and partition polynomials of the sort I illustrate. Some OEIS reductions/specializations below reference a more directly related paper by Paul Barry. Btw, you might already know this, but the $[A^{(m}]$ and $[N]^m$ form a realization of an infinite dihedral grp, which is interesting since finite dihedral groups are used in the Coxeter group formalism to characterize the associahedra and noncrossing partitions. I posted an MSE-Q on this.
Jul 30, 2023 at 20:07 comment added Sam Hopkins I don't know if it is directly related to your question, but you might be interested in the "pseudo-involutions in the Riordan group": see, e.g., arxiv.org/abs/2112.11595
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Mar 23, 2023 at 18:23 comment added Tom Copeland Adjusting the overall sign of a polynomial, the involution III is eqn 1.3 on p. 70 of "Lagrange Inversion and Schur Functions" by Lenart, who references "Symmetric Functions and Hall Polynomials" by Macdonald (p. 35, Ex. 24).
Feb 25, 2023 at 18:04 history edited Tom Copeland CC BY-SA 4.0
Elaborated on definitions
Feb 25, 2023 at 11:54 comment added YCor Starting the post with a definition of "involution" might be useful.
Feb 25, 2023 at 2:05 answer added Tom Copeland timeline score: 0
Jun 26, 2022 at 16:11 comment added Tom Copeland Example III--essentially Schur's self-convolution expansion coefficients $-b_(n+1)=\frac{K_{n+1,n}}{n}$, or $\frac{K_{n+1}^(n)}{n}$--to be characterized in A355201.
Jun 26, 2022 at 4:09 history edited Tom Copeland CC BY-SA 4.0
Dependency on a_0 corrected.
Jun 11, 2022 at 20:03 history edited Tom Copeland CC BY-SA 4.0
Expanded set of indeterminates for last example, changed a tag
Jun 11, 2022 at 3:55 history edited Tom Copeland CC BY-SA 4.0
Added new involution
May 17, 2022 at 17:32 comment added Tom Copeland @SamHopkins: The relations among the LIF, the LPT, and compositional polynomials such as the Bell partition polynomials, OEIS A036040, are given in my pdf "Lagrange a la Lah" (2011). The partition polynomials that are inverse to the Bell are noted in the OEIS entry.
May 14, 2022 at 20:50 comment added Tom Copeland @SamHopkins: Certainly related to the Bell polynomials and similar compositional partition polynomials, but the CPPs don't provide an involution since $f(g(x))$ is not typically the same as $g(f(x))$.
May 14, 2022 at 20:43 comment added Tom Copeland @SamHopkins, the o.g.f. version of example I, A263633 as noted in the example, covers the elementary and complete homogeneous functions (see my related comment in that OEIS entry.)
May 14, 2022 at 20:41 comment added Sam Hopkins Sorry, maybe that is exactly the same as your example #1.
May 14, 2022 at 19:54 comment added Sam Hopkins Maybe the involution $\omega$ on the ring $\Lambda$ of symmetric functions which swaps the elementary $e_n$ and complete homogeneous $h_n$ symmetric functions would give another natural example.
May 14, 2022 at 17:43 history asked Tom Copeland CC BY-SA 4.0