Abstract
We prove that the overpartition function \( \overline{p}(n)\) is log-concave for all \( n\ge 2 \). The proof is based on Sills-Rademacher-type series for \( \overline{p}(n)\) and inspired by DeSalvo and Pak’s proof for the partition function.
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DeSalvo, S., Pak, I.: Log-concavity of the Partition Function. (2013)
Hardy, G.H., Ramanujan, S.: Asymptotic formulaæ in combinatory analysis. Proc. Lond. Math. Soc. 2(1), 75–115 (1918)
Lehmer, D.H.: On the series for the partition function. Trans. Amer. Math. Soc. 43(2), 271–295 (1938)
Rademacher, H.: On the partition function p(n). Proc. Lond. Math. Soc. 2(1), 241–254 (1938)
Sills, A.V.: A Rademacher type formula for partitions and overpartitions. Int. J. Math. Math. Sci. 2010, 21 (2010). doi:10.1155/2010/630458
Zuckerman, H.S.: On the coefficients of certain modular forms belonging to subgroups of the modular group. Trans. Am. Math. Soc 45(2), 298–321 (1939)
Acknowledgments
The author is grateful for useful advice and guidance from Professor Bringmann, Dr. Krauel, Dr. Li, Dr. Mertens, and Dr. Rolen.
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Engel, B. Log-concavity of the overpartition function. Ramanujan J 43, 229–241 (2017). https://doi.org/10.1007/s11139-015-9762-0
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DOI: https://doi.org/10.1007/s11139-015-9762-0