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arXiv · 2605.08304

Combinatorics of higher order degenerate $r$-DERANGED Bell Numbers

Sithembele Nkonkobe
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Abstract

When one inserts a number of identical bars in between blocks of an ordered set partition, they obtain a barred preferential arrangement. In this study we define a new generalization of barred preferential arrangements, by considering barred preferential arrangements with no fixed blocks, and where $r$ fixed elements on each section of the barred preferential arrangement are singletons. We derive several combinatorial identities for the number of these barred preferential arrangements. We also provide some asymptotic results.

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Sithembele Nkonkobe. 2026-05-08. Combinatorics of higher order degenerate $r$-DERANGED Bell Numbers. https://arxiv.org/abs/2605.08304

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