Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| * 508: | \[{21^{508}-1\over20}\] | 22 × 11 × 13 × 17 × 509 × 3049 × 3557 × 85853 × 256033 × 985013 × 123564234215209<15> × 526073566316093<15> × 21045416332383383<17> × 3023767784043644159<19> × 525212323217088996809<21> × 14948184961120158829387<23> × 6619201108364006378440292620708869500505245589624095987<55> × 105546738449008968050440888723415799976700232611051102641043<60> × 524564045386279138033219804241183578649565761983063373697101770052236095818825177938399303025183058937<102> × [1759773691092964124691826428650905063685196950811218035416992345665771142414470964654999718356200376481149593427582824335764700035205312068296133218367728814155788244351144703811496400991778039499895960779157540083544048699410732776039151422536918105845084750675847113105916217515979183203491205539157668588184435190657<319>] |