A105756 Indices of prime Fibonacci 5-step numbers, A001591.

3, 7, 8, 25, 146, 169, 182, 751, 812, 1507, 1591, 3157, 3752, 10651, 12740, 71804, 155953

Offset: 1

Author

T. D. Noe, Apr 22 2005

Keywords

• nonn

Comments

No other n < 44000.

The Noe and Post reference below utilizes a scheme for its indices which differs by 3 from the indices in A001591. - Robert Price, Oct 13 2014

The sequence is similar to A248757 which uses the indexing scheme starting at 0 as defined by A001591. - Robert Price, Oct 13 2014

a(18) > 2*10^5. - Robert Price, Oct 13 2014

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, Fibonacci n-Step Number

Crossrefs

Cf. A105757 (prime Fibonacci 5-step numbers).

Programs

Mathematica

a = {1, 0, 0, 0, 0}; lst = {}; Do[s = Plus @@ a; a = RotateLeft[a];
  a[[-1]] = s; If[PrimeQ[s], AppendTo[lst, n]], {n, 44000}]; lst
Flatten[Position[LinearRecurrence[{1,1,1,1,1},{0,0,0,0,1},13000],?PrimeQ]]-4 (* _Harvey P. Dale, Mar 06 2023 *)

Extensions

Restored original sequence after reconsideration and added a(16)-a(17) by Robert Price, Oct 13 2014