🌐EnglishEnglishDeutschEspañolFrançaisItalianoPolskiPortuguêsРусскийالعربيةفارسیहिन्दी中文日本語EntityQ3502995· pop 15· linked from 505 articlesundecidable problemdecision problem for which it is impossible to construct an algorithm that always leads to a correct yes-or-no answerAvailable in 15 languagesEspañolFrançais中文РусскийPortuguêsالعربيةहिन्दीArmenianBulgarianConnectionssemantic theory of truthEntitynatural numberEntityCategoriesComputability theoryLogic in computer scienceUndecidable problems