Base 20 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
158: | \[{20^{158}-1\over19}\] | 3 × 7 × 26861 × 7731160503875069<16> × 4178614725165165091<19> × 52283868973702536169<20> × 7012116809755762514267308698568975988864311<43> × 287839480860625993977660952380952380952380952380952380952380952380952380952380952380952380952380952381<102> |