Primitive and geometric-progression-free sets without large gaps
Volume 192 / 2020
                    
                    
                        Acta Arithmetica 192 (2020), 95-104                    
                                        
                        MSC: Primary 11N25; Secondary 11B05.                    
                                        
                        DOI: 10.4064/aa180921-4-2                    
                                            
                            Published online: 26 September 2019                        
                                    
                                                Abstract
We prove the existence of primitive sets (sets of integers in which no element divides another) in which the gap between any two consecutive terms is substantially smaller than the best known upper bound for the gaps in the sequence of prime numbers. The proof uses the probabilistic method. Using the same techniques we improve the bounds obtained by He for gaps in geometric-progression-free sets.