n!!!! + 1
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 209: | \[209!!!!+1\] | 2 × 4345031 × 354762114384074767<18> × 504441752541430303013<21> × 3125901440684861921462694054877200916960873445099090513<55> |