Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 288: | \[{21^{288}-1\over20}\] | 25 × 11 × 13 × 17 × 19 × 37 × 61 × 73 × 97 × 193 × 199 × 421 × 433 × 463 × 613 × 673 × 1217 × 1693 × 2689 × 3181 × 31873 × 62897 × 97241 × 300673 × 816769 × 1001713 × 25392481 × 85775383 × 518118697 × 808208209 × 6857635489<10> × 2280879799777<13> × 4344847859197<13> × 5024477501569<13> × 4116371120264449<16> × 81967288802253121<17> × 93310250563834657<17> × 226108215051938888394049<24> × 711232550734200751494958531511588181663062004769<48> × 747926617936738238652286330798949662845703840819895673338678850871550518197590173394784787747281609697<102> |