Base 3 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 281: | \[{3^{281}-1\over2}\] | 563 × 3373 × 422063 × 434989 × 1000081249 × 38012519036699<14> × 124205327610431<15> × 543615007915184215523<21> × 2397212236344676495763<22> × 27451255028998486919447695885731956353<38> |