Abstract
Using combinatorial methods we study the structural coefficients of the formal homogeneous universal enveloping algebra \(\widehat{U}_h({\mathfrak {sl}}_2) \) of the special linear algebra \( {\mathfrak {sl}}_2\) over a characteristic zero field. We provide explicit formulae for the product of generic elements in \( \widehat{U}_h({\mathfrak {sl}}_2),\) and construct combinatorial objects giving flesh to these formulae; in particular, we provide explicit formulae and combinatorial interpretations for the structural coefficients of divided power Poincaré–Birkhoff–Witt basis.
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Acknowledgements
E. Salamanca was partially supported by a “Young Researcher” − COLCIENCIAS grant.
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Díaz, R., Salamanca, E. On the combinatorics of the universal enveloping algebra \(\widehat{U}_h({{\mathfrak {sl}}}_2)\). São Paulo J. Math. Sci. 13, 342–369 (2019). https://doi.org/10.1007/s40863-018-0088-x
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DOI: https://doi.org/10.1007/s40863-018-0088-x