Base 28 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| * 215: | \[{28^{215}-1\over27}\] | 1291 × 3613 × 60029 × 208121 × 637421 × 684217 × 105942074311<12> × 23321405465263<14> × 17068111104046291434149<23> × [4758969016453637749130395132989308308067773353739149421025330266741721818685352637933870548175818490954671502785265694439498583882067602732219365268057998063986604547023936387363547025518238994703771873719794235865410693640414699462151<235>] |