Base 31 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 87: | \[{31^{87}-1\over30}\] | 3 × 331 × 349 × 2437 × 10789 × 29581 × 49823 × 6226417 × 24589681 × 1482570191 × 11242578713<11> × 19442411479<11> × 189343400041<12> × 1480537408333241006942871103432327233924912298742791<52> |