Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| * 400: | \[{21^{400}-1\over20}\] | 24 × 52 × 11 × 13 × 17 × 41 × 101 × 241 × 401 × 1601 × 9521 × 19501 × 40841 × 56501 × 62897 × 97241 × 185641 × 300673 × 2031851 × 3441241 × 4141001 × 11093851 × 22995281 × 33534961 × 920421641 × 1166256601 × 3184193681 × 35270582801<11> × 363230092241<12> × 33360993558601<14> × 415710882920521<15> × 72215141710303601<17> × 248303068144516751<18> × 27385718497004633851<20> × 1996182264216434668032401<25> × 2105812970476039816410905651801<31> × 35174788322661027467540897515852263605666386954957467123897302082814391146412401<80> × [387902869635527801122080250106854593639075308080011539982467601629254570367524421104031238514188635058931705998597549146797209548712817769081597685206005707997647601<165>] |