Abstract
In the paper, the authors intrinsically observe that Hoffman’s combinatorial identity discovered in 1992 and Genčev’s combinatorial identities extended in 2024 can be reformulated in terms of complete Bell polynomials. They provide alternative proofs and offer some elementary generalizations of these combinatorial identities.
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Acknowledgements
The authors are thankful to Dave L. Renfro (Coralville, IA, USA) for his recommendation of the monograph [5] on 26 October 2023. The authors appreciate the anonymous referees for their valuable comments, helpful suggestions, and careful corrections to the original version of this paper.
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The first author was partially supported by the Key Construction and Characteristic Cultivation Discipline Construction Project of Hulunbuir University (Grant No. 2023XKJS38).
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He, CY., Qi, F. Reformulations and Generalizations of Hoffman’s and Genčev’s Combinatorial Identities. Results Math 79, 131 (2024). https://doi.org/10.1007/s00025-024-02160-0
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DOI: https://doi.org/10.1007/s00025-024-02160-0
Keywords
- Reformulation
- generalization
- combinatorial identity
- complete bell polynomial
- Faà di Bruno formula
- Catalan number
- Bernoulli number
- Euler number
- central factorial number
- sine
- cosine
- series expansion