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arXiv · 1703.08826

Counting faces of nestohedra

Vladimir Grujić·Tanja Stojadinović
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Abstract

A new algebraic formula for the numbers of faces of nestohedra is obtained. The enumerator function $F(P_B)$ of positive lattice points in interiors of maximal cones of the normal fan of the nestohedron $P_B$ associated to a building set $B$ is described as a morphism from the certain combinatorial Hopf algebra of building sets to quasisymmetric functions. We define the $q$-analog $F_q(P_B)$ and derive its determining recurrence relations. The $f$-polynomial of the nestohedron $P_B$ appears as the principal specialization of the quasisymmetric function $F_q(P_B)$.

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Vladimir Grujić, Tanja Stojadinović. 2017-10-22. Counting faces of nestohedra. https://arxiv.org/abs/1703.08826

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