n!!!! + 1
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
305: | \[305!!!!+1\] | 2 × 8681 × 1603067992830647287033527187<28> × 1262423943470368035862916057336080393643738963631703764848142001569316342803611629584164422502097524134515765200868248195143279<127> |