Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 38: | \[{21^{38}-1\over20}\] | 2 × 11 × 609673 × 12061389013<11> × 54921106624003<14> × 987749814642143197<18> |
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 38: | \[{21^{38}-1\over20}\] | 2 × 11 × 609673 × 12061389013<11> × 54921106624003<14> × 987749814642143197<18> |