n!! - 1
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
159: | \[159!!-1\] | 25 × 647 × 8918131 × 4605484991801445772067087<25> × 376102821484381933443461188963878951054014672923<48> × 17038007133619505729018333241724261620750753755365930803301<59> |