n!!!! + 1
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
299: | \[299!!!!+1\] | 23 × 45533 × 78541 × 14406559030836420858607<23> × 23792865992418336456725237795453406290230318570991614899748400362372598141688117679008536041084409196984763614655824166657<122> |