Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
100: | \[{21^{100}-1\over20}\] | 22 × 52 × 11 × 13 × 17 × 41 × 101 × 19501 × 40841 × 56501 × 185641 × 2031851 × 11093851 × 920421641 × 33360993558601<14> × 248303068144516751<18> × 27385718497004633851<20> × 2105812970476039816410905651801<31> |