On Some Conjectures by Rabinowitz

Krzysztof Kolodziejczyk1, Daria Olszewska2
1Institute of Mathematics, Wroclaw University of Technology Wybrzeze Wyspiariskiego 27, 50-370 Wroclaw, Poland
2 Institute of Mathematics, Wroclaw University of Technology Wybrzeze Wyspiariskiego 27, 50-370 Wroclaw, Poland

Abstract

Working on the problem of finding the numbers of lattice points inside convex lattice polygons, Rabinowitz has made several conjectures dealing with convex lattice nonagons and decagons. An intensive computer search preceded a formulation of the conjectures. The main purpose of this paper is to prove some of Rabinowitz’s conjectures. Moreover, we obtain an improvement of a conjectured result and give short proofs of two known results.