The aim of this paper is the investigation of weakly H-quasiconvex functions in the framework of the Heisenberg group H\mathbb{H}. The functions of this class, recently introduced by M. B. Sun and X. P. Yang ["Some properties of quasiconvex functions on the Heisenberg Group", Acta Math. Appl. Sinica 21 (2005) 571–580], are defined via the property that their sublevels are weakly H-convex subsets of H\mathbb{H}. Following Crouzeix's approach, we prove conditions of first and second order, easily testable, for regular weakly H-quasiconvex functions, and we provide a characterization of them.

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Andrea Calogero

Dip. di Statistica, Università di Milano-Bicocca, Via Bicocca degli Arcimboldi 8, 20126 Milano, Italy

andrea.calogero@unimib.it

Giovanna Carcano

Dip. di Metodi Quantitativi per le Scienze Economiche ed Aziendali, Università di Milano-Bicocca, Piazza Ateneo Nuovo 1, 20126 Milano, Italy

giovanna.carcano@unimib.it

Rita Pini

Dip. di Metodi Quantitativi per le Scienze Economiche ed Aziendali, Università di Milano-Bicocca, Piazza Ateneo Nuovo 1, 20126 Milano, Italy

rita.pini@unimib.it
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A. Calogero, G. Carcano, R. Pini. “On Weakly H-Quasiconvex Functions on the Heisenberg Group.” Journal of Convex Analysis 15 (2008), No. 4, 753–766. https://doi.org/10.68381/jca15050