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>
| 680: | \[L_{680}\] | 47 × 1601 × 3041 × 1376321 × 9830081 × 280381350009601<15> × 2843304747267841<16> × 616713904085105580641<21> × 562627837283291940137654881<27> × 15098556848842849848964622710079616350508641<44> |