Base 4 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 337: | \[{4^{337}-1\over3}\] | 18199 × 21569 × 2806537 × 5333388961<10> × 95763203297<11> × 726584894969<12> × 964094242760707<15> × 78778047326466742993612420842416198311394008068822475527239136925369<68> × 841462035388400254709200130801140475354660321983340709246797058685767257<72> |