2025/09/16 by Yorick Herrmann, Herrmann, Yorick, Hill, Connor +7
Mathematics · Engineering · Computer Science · #Limits and Structures in Graph Theory #graph theory and CDMA systems #Advanced Graph Theory Research
paper · pdf · doi:10.48550/arxiv.2509.12829
A More Sums Than Differences (MSTD) set is a finite set of integers A where the cardinality of its sumset, A+A, is greater than the cardinality of its difference set, A-A. We address a problem posed by Samuel Allen Alexander that asks whether there exists an infinite sequence of sets alternating between being MSTD and More Differences Than Sums (MDTS), where each set properly contains the previous. While a companion paper resolved this using `filling in' techniques, we solve the more challenging `non-filling-in' version, where any missing integer between a set's minimum and maximum elements remains missing in all subsequent sets.