Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 47: | \[{21^{47}-1\over20}\] | 49727 × 227011 × 75042551 × 158545759 × 5298873343<10> × 9794718038248648833094153<25> |
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 47: | \[{21^{47}-1\over20}\] | 49727 × 227011 × 75042551 × 158545759 × 5298873343<10> × 9794718038248648833094153<25> |