Base 20 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 136: | \[{20^{136}-1\over19}\] | 3 × 7 × 137 × 401 × 2857 × 3673 × 160001 × 2567783 × 2640509 × 92054423 × 629433157137881<15> × 230734661278799273<18> × 689852631578947368421<21> × 680653156857066936553996121<27> × 2878870785836948026295038313<28> × 193165810175918904613943865257<30> |