Lattice triangles with certain properties
Source: Kvant Magazine No. 9 2020 M2619
March 9, 2023
geometrylattice pointsKvant
Problem Statement
Let be non-negative integers. A triangle on a checkered plane with vertices in the nodes of the grid is called an -triangle if there are exactly nodes on one side of it (not counting vertices), exactly nodes on the second side, and exactly nodes on the third side.[*]Does there exist a -triangle?
[*]Find all triples of non-negative integers for which there exists an -triangle.
[*]For each such triple, find the minimum possible area of the -triangle.Proposed by P. Kozhevnikov