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>
253: | \[L_{253}\] | 139 × 199 × 461 × 13343097459037867049<20> × 439589715274978576995097049<27> |