English

The sad life of lattice triangles

Combinatorics 2026-03-02 v1

Abstract

This paper treats triangles in the plane whose vertices lie on the integer lattice, i.e., the vertices have integer coordinates. It shows that apart from trivial examples, the circumcenter, centroid and orthocenter of such triangles never all lie on the integer lattice. Several further observations are made concerning the circumcenter, centroid and orthocenter.

Keywords

Cite

@article{arxiv.2602.23392,
  title  = {The sad life of lattice triangles},
  author = {Christian Aebi and Grant Cairns},
  journal= {arXiv preprint arXiv:2602.23392},
  year   = {2026}
}