n!! - 1
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 237: | \[237!!-1\] | 2 × 10259 × 8147583449<10> × 9020535390441760089964249<25> × 5886432787059548878588050689<28> × 215639904502497270128663801558394350898465655620583078474961598584584450438984906455392038638774513187732855720801807215065757630993301887569929565175573404671854437<165> |