Thrall’s problem asks for the Schur decomposition of the higher Lie modules $\mathcal{L}_\lambda $, which are defined using the free Lie algebra and decompose the tensor algebra as a general linear group module. Although special cases have been solved, Thrall’s problem remains open in general. We generalize Thrall’s problem to the free Lie superalgebra, and prove extensions of three known results in this setting: Brandt’s formula, Klyachko’s identification of the Schur–Weyl dual of $\mathcal{L}_n$, and Kráskiewicz–Weyman’s formula for the Schur decomposition of $\mathcal{L}_n$. The latter involves a new version of the major index on super tableaux, which we show corresponds to a $q,t$-hook formula of Macdonald.
Accepted:
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Keywords: free Lie superalgebras, Thrall’s problem, major index, super tableaux
Armon, Sam 1; Swanson, Joshua P. 1

@article{ALCO_2025__8_3_795_0, author = {Armon, Sam and Swanson, Joshua P.}, title = {Super major index and {Thrall{\textquoteright}s} problem}, journal = {Algebraic Combinatorics}, pages = {795--815}, publisher = {The Combinatorics Consortium}, volume = {8}, number = {3}, year = {2025}, doi = {10.5802/alco.421}, language = {en}, url = {https://alco.centre-mersenne.org/articles/10.5802/alco.421/} }
TY - JOUR AU - Armon, Sam AU - Swanson, Joshua P. TI - Super major index and Thrall’s problem JO - Algebraic Combinatorics PY - 2025 SP - 795 EP - 815 VL - 8 IS - 3 PB - The Combinatorics Consortium UR - https://alco.centre-mersenne.org/articles/10.5802/alco.421/ DO - 10.5802/alco.421 LA - en ID - ALCO_2025__8_3_795_0 ER -
Armon, Sam; Swanson, Joshua P. Super major index and Thrall’s problem. Algebraic Combinatorics, Volume 8 (2025) no. 3, pp. 795-815. doi : 10.5802/alco.421. https://alco.centre-mersenne.org/articles/10.5802/alco.421/
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