OFFSET
1,1
COMMENTS
a(36) > 2*10^5.
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
MATHEMATICA
a={1, 1, 1, 1}; For[n=4, n<=1000, n++, sum=Plus@@a; If[PrimeQ[sum], Print[n]]; a=RotateLeft[a]; a[[4]]=sum]
Flatten[Position[LinearRecurrence[{1, 1, 1, 1}, {1, 1, 1, 1}, 10^5], _?PrimeQ]]- 1 (* Harvey P. Dale, Dec 20 2016 *)
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Robert Price, Sep 27 2014
STATUS
approved