n!!!!! + 1
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
301: | \[301!!!!!+1\] | 521 × 22543 × 15843491 × 520928548640293<15> × 184276350170628809173987213920663262058373598669863533498827819629908851468573245188996510559193<96> |