Lucas Sequence
Defined with \(L_0=2\), \(L_1=1\), and \(L_n=L_{n-1}+L_{n-2}\) when \(n\geq2\). Related to the Fibonacci sequence.
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 639: | \[L_{639}\] | 22 × 19 × 1279 × 1882921 × 635099565380941<15> × 688846502588399<15> × 49258624519847932639<20> × 8853996174522467507283350064621808292949041096316622294281677406409417861<73> |