Base 31 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
72: | \[{31^{72}-1\over30}\] | 27 × 32 × 72 × 13 × 19 × 37 × 73 × 331 × 409 × 577 × 1129 × 3637 × 81343 × 922561 × 1536553 × 1538083 × 4683817 × 512616735577<12> × 852890113921<12> × 1814503763676130449408979921<28> |