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arXiv · 1312.7185

The first elements of the quotient of a numerical semigroup by a positive integer

Alessio Moscariello
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Abstract

Given three pairwise coprime positive integers $a_1,a_2,a_3 \in \mathbb{Z}^+$ we show the existence of a relation between the sets of the first elements of the three quotients $\frac{\langle a_i,a_j \rangle}{a_k}$ that can be made for every $\{i.j,k\}=\{1,2,3\}$. Then we use this result to give an improved version of Johnson's semi-explicit formula for the Frobenius number $g(a_1,a_2,a_3)$ without restriction on the choice of $a_1,a_2,a_3$ and to give an explicit formula for a particular class of numerical semigroups.

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Alessio Moscariello. 2013-12-27. The first elements of the quotient of a numerical semigroup by a positive integer. https://doi.org/10.1007/s00233-014-9600-5

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