On the Möbius function of the locally finite poset associated with a numerical semigroup

Jonathan Chappelon, Jorge Ramírez Alfonsín

Let $S$ be a numerical semigroup and let $\left(\mathbb{Z},⩽\_S\right)$ be the (locally finite) poset induced by $S$ on the set of integers $\mathbb{Z}$ defined by $x \leqs…