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arXiv · 1812.02955

Mixed restricted Stirling numbers

Somaya Barati·Beáta Bényi·Abbas Jafarzadeh·Daniel Yaqubi
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Abstract

In this note we investigate mixed partitions with extra condition on the sizes of the blocks. We give a general formula and the generating function. We consider in more details a special case, determining the generating functions, some recurrences and a connection to r-Stirling numbers. To obtain our results, we use pure combinatorial arguments, classical manipulations of generating functions and to derive the generating functions we apply the symbolic method.

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Somaya Barati, Beáta Bényi, Abbas Jafarzadeh, Daniel Yaqubi. 2018-12-07. Mixed restricted Stirling numbers. https://arxiv.org/abs/1812.02955

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