Base 13 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 79: | \[{13^{79}-1\over12}\] | 3793 × 16433 × 6709792556882923<16> × 1999561631486182208460037804951465687912381337222920142652723329<64> |