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A105756
Indices of prime Fibonacci 5-step numbers, A001591.
4
3, 7, 8, 25, 146, 169, 182, 751, 812, 1507, 1591, 3157, 3752, 10651, 12740, 71804, 155953
OFFSET
1,1
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
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 *)
CROSSREFS
Cf. A105757 (prime Fibonacci 5-step numbers).
Sequence in context: A102007 A152486 A301523 * A152057 A177689 A191611
KEYWORD
nonn
AUTHOR
T. D. Noe, Apr 22 2005
EXTENSIONS
Restored original sequence after reconsideration and added a(16)-a(17) by Robert Price, Oct 13 2014
STATUS
approved