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November 09 The Refined Lives of the F- and H-Vectors of AssociahedraThe compositional inversions noted in the Oct. 9-th entry "Flipping October 09 Flipping Functions with PermutohedraFlipping Functions with Permutohedra A short note on forming the multiplicative and compositional inverses of functions using the refined Eulerian h-polynomials and refined face polynomials of permutohedra. September 28 Combinatorics of OEIS-A074060The notes Combinatorics of OEIS-A074060 sketch how combinatorial interpretations of LaGrange inversion and the 2-restricted Stirling numbers of the first kind provide a combinatorial construction for the array OEIS-A074060 (Graded dimension of the cohomology ring of the moduli space of n-pointed curves of genus 0 satisfying the associativity equations of physics). September 13 Short Note on Lagrange InversionShort Note on Lagrange Inversion is an addendum to OEIS-A134685. June 12 Mathemagical ForestsThe set of notes Mathemagical Forests is an expansion of the May notes and discusses some connections between rooted trees, derivative operators, Lagrange inversion, the Legendre transformation, the Faa di Bruno formula, Sheffer sequences and umbral calculus, and the infinite Witt Lie algebra. May 09 A Walk in the Woods with Cayley and ComtetIn the last several months, I've been exploring the connections between umbral calculus and integer sequences and have published several items, searchable under the name Tom Copeland, in the Online Encyclopedia of Integer Sequences (OEIS). During the process, I became aware of the ubiquitousness of trees in combinatorics and found it useful to go back to the origins to get a good feel for them. The resulting set of notes "A Walk in the Woods with Cayley and Comtet " might be a helpful introduction to others on some elementary relations between the infinitesimal calculus and rooted trees ala Cayley.
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