n!!!! + 1
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
300: | \[300!!!!+1\] | 36919 × 28418782132610673022423<23> × 378660084158250608882983<24> × 511607194243252601914868311<27> × 174208568460238028893188620498016029752755056383434383951982126027525464683921<78> |