n!! + 1
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 123: | \[123!!+1\] | 22 × 1811 × 8053 × 33247 × 8945556072103763123004363398209439962933<40> × 598155077066437068295130928912862640902039478455343<51> |