n!! - 1
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| * 255: | \[255!!-1\] | 28 × 6709 × 6789037 × 56223649 × 1975395577 × [5047966503143206966620254914413764045628613506146810688972268578167133660411019081471513403598337434153475996655444479298654102641422340526031514060889534213316493215044788717878485447018912269335314726864185530954832431281<223>] |