🌐EnglishEnglishEspañolFrançaisItalianoРусский한국어日本語EntityQ649322· pop 9· linked from 7 articlesZnám's problemthe problem of finding sets of integers in which each is a proper divisor of one plus the product of the othersAvailable in 9 languagesEspañolFrançaisРусскийItalianoCatalanHungarianzh_yue한국어via Wikidata sitelinks · CC0ConnectionsareaEntityprime numberEntityCategoriesEgyptian fractionsInteger sequencesMathematical problemsNumber theory