EntityQ5607239· pop 5· linked from 15 articlesGregory numberSign in to saveConnectionsmathematicsEntitynumber theoryEntityreal numberEntityrational numberEntityirrational numberEntitysubsetEntity0.999...Entitynumber lineEntityinverse trigonometric functionEntitypower seriesEntityJohn Horton ConwayEntityJames GregoryEntityCantor setEntitynormal numberEntityLeibniz formula for πEntityRichard K. GuyEntityextended real number lineEntityVitali setEntitycompleteness of the real numbersEntityconstruction of the real numbersEntityCategoriesSets of real numbers