Base 7 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 128: | \[{7^{128}-1\over6}\] | 29 × 52 × 17 × 353 × 1201 × 35969 × 169553 × 7699649 × 134818753 × 47072139617<11> × 531968664833<12> × 1110623386241<13> × 15266848196793556098085000332888634369<38> |