n!!!! + 1
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
231: | \[231!!!!+1\] | 2 × 97 × 59299687241<11> × 41311031739355404630825787<26> × 121307917337359160777111470858490292196026541737540881459369980173548964337<75> |