Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 342: | \[{21^{342}-1\over20}\] | 2 × 11 × 192 × 37 × 199 × 421 × 463 × 613 × 28387 × 304609 × 609673 × 5285953 × 67505443 × 85775383 × 3263277133 × 12061389013<11> × 54921106624003<14> × 89287241422177<14> × 1769098309517989<16> × 987749814642143197<18> × 1343456427753441154701241543<28> × 201773586986282524421768503820293<33> × 1168393184916024427650240126995059<34> × 6553440934433074491786184400208956951461<40> × 1244541772187848099210936765314595053007129<43> × 4221771679991568872140247488173084599918532628921398895938769<61> × 1906545596109201001931181173321063934469362055720076288290431439788614388343220743<82> |