A Combinatorial Model for q-Generalized Stirling and Bell Numbers
Miguel Méndez, Adolfo Rodríguez
Abstract
We describe a combinatorial model for the q-analogs of the generalized Stirling numbers in terms of bugs and colonies. Using both algebraic and combinatorial methods, we derive explicit formulas, recursions and generating functions for these q-analogs. We give a weight preserving bijective correspondence between our combinatorial model and rook placements on Ferrer boards. We outline a direct application of our theory to the theory of dual graded graphs developed by Fomin. Lastly we define a natural p,q-analog of these generalized Stirling numbers.
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