Base 31 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| * 221: | \[{31^{221}-1\over30}\] | 42407 × 251057 × 2426789 × 7908811 × 485975954621<12> × 751670559138758105956097<24> × [174107572581561294640637318836696690042273196879268538342185383758875383118151464356875961105680163080694108902001474161895083866638094457164437711293871138432212839257480542808547018859834361457599643171975315560367438335752953124844849944297687805162779605834099399973<270>] |