The numbers 1-7 are disposed among the regions in this figure such that each of the circular sets yields the same sum. This makes it a “magic Venn diagram,” a concept that occurred to mathematician David Robinson while teaching a course in mathematical logic at the University of West Georgia. His article appears in the December 2025 issue of Recreational Mathematics Magazine.

(David Robinson and Anja Remshagen, “Magic Venn Diagrams,” Recreational Mathematics Magazine 12:21 [December 2025], 25-44.)