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>
| 391: | \[L_{391}\] | 139 × 461 × 3571 × 10949 × 2476673936041<13> × 834484880498372128537891307445941852925566419249911616229<57> |