3 papers
cs.DM2026
A new proof of Delahan's induced-universality result
Jonathan Chappelon
We give a short and self-contained proof of Delahan's theorem stating that every simple graph on vertices occurs as an induced subgraph of a Steinhaus graph on $\frac{n(n-1)}{2…
math.AC2025
Numerical semigroup tree: type-representation
Jonathan Chappelon, Jorge L. RamÃrez AlfonsÃn, Dumitru I. Stamate
In this paper, we introduce a new depicting of the so-called numerical semigroup tree . By exploring computationally this improved picture, relying on the type notion o…
math.CO2025
Balanced Steinhaus triangles
Jonathan Chappelon
A Steinhaus triangle modulo is a finite down-pointing triangle of elements in the finite cyclic group satisfying the same local rule as the standard Pa…