Base 15 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 197: | \[{15^{197}-1\over14}\] | 3547 × 4172753531 × 2898371050355248441<19> × 1628637743047903281357843380265934783<37> × 5007115369239966965453632933099494048800475080967921090792452689575106437727933345923966054160696194307198860440992223900744789097704999380341785552242370357593871<163> |