A105762 Primes in A001644 (the Lucas 3-step numbers).

3, 7, 11, 71, 131, 241, 443, 1499, 196331, 86992799, 541292033, 292997064989357251, 129824812729295169371, 238785058551151434437, 5026368970977284897651, 105803877284856287511991

Offset: 1

Author

T. D. Noe, Apr 22 2005

Keywords

• nonn

Links

• Tony D. Noe and Jonathan Vos Post, Primes in Fibonacci n-step and Lucas n-step Sequences, J. of Integer Sequences, Vol. 8 (2005), Article 05.4.4
• Eric Weisstein's World of Mathematics, Lucas n-Step Number

Crossrefs

Cf. A104576 (indices of prime Lucas 3-step numbers).

Programs

Mathematica

a={-1, -1, 3}; lst={}; Do[s=Plus@@a; a=RotateLeft[a]; a[[ -1]]=s; If[PrimeQ[s], AppendTo[lst, s]], {n, 1000}]; lst

Formula

a(n) = A001644(A104576(n)). - Arthur O'Dwyer, Jul 31 2024

Extensions

Name clarified by Arthur O'Dwyer, Jul 31 2024