n!!!! - 1
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
261: | \[261!!!!-1\] | 22 × 20969213 × 21710201 × 7165489423<10> × 25309771127<11> × 177213349241663183<18> × 602338250007695344394535058886187621976144593168250847005784087684307546519659<78> |