n!! - 1
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
161: | \[161!!-1\] | 26 × 383 × 9911675549646809<16> × 1449323693251793929<19> × 3402209266076849143<19> × 732322707476392075509542771930802116957853504355708171033127757653202449748929501728049<87> |