n!!!! + 1
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
248: | \[248!!!!+1\] | 18111140089771<14> × 22963838639676134699<20> × 89879980444415740543<20> × 17904516207931710136468756039223619883573257673650963067071705835553783<71> |