Abstract
In this paper, we propose a q-analogue of the number of permutations i(n, k) of length n having k inversions known by Mahonian numbers. We investigate useful properties and some combinatorial interpretations by lattice paths/partitions and tilings. Furthermore, we give two constructive proofs of the strong q-log-concavity of the q-Mahonian numbers in k and n, respectively. In particular for \(q=1\), we obtain two constructive proofs of the log-concavity of the Mahonian numbers in k and n, respectively.
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Acknowledgements
The authors would like to thank the referees for many valuable remarks and suggestions to improve the original manuscript. This work was supported by DG-RSDT (Algeria), PRFU Project, No. C00L03UN180120220002.
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Communicated by Ken Ono.
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Ghemit, Y., Ahmia, M. An Analogue of Mahonian Numbers and Log-Concavity. Ann. Comb. 27, 895–916 (2023). https://doi.org/10.1007/s00026-022-00614-2
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DOI: https://doi.org/10.1007/s00026-022-00614-2