Base 7 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 277: | \[{7^{277}-1\over6}\] | 137947 × 8954857 × 607705768105925529871<21> × 1008546397779986402744853280052751256841864202057421515367093607755446588358126544676145969493651<97> × 272173399268373465997780937070771744096205106935430177416308863871029236235363341081142961347363607152039<105> |