n!!!! + 1
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 273: | \[273!!!!+1\] | 2 × 1847 × 58485316935499392840495864262881316845289<41> × 3175367406031724452180777661304893739781175709167971028020965175732748435728826070215881201411<94> |