n!! - 1
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 154: | \[154!!-1\] | 2393 × 23857 × 2779924028267<13> × 3571748599782604547<19> × 595844366714277787403729203<27> × 64956188015566893804286710497686706818441309147147532909804719469617117<71> |