n# + 1
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
56: | \[263\#+1\] | 271 × 19891019 × 3957327431 × 25098482428840021840888422712477<32> × 8113282654295184016384291170580044761513684462631090637<55> |