Base 13 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 69: | \[{13^{69}-1\over12}\] | 3 × 61 × 139 × 1381 × 10903 × 282244620282733<15> × 2519545342349331183143<22> × 22271867346104672186904295489<29> |