n!!!! + 1
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
278: | \[278!!!!+1\] | 1305547252239547<16> × 4002535793979359177380284229<28> × 215068662140893373074192028791883941076778264576594304528939863194249378036807436561568068164362327<99> |