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Indices of primes in the 7th-order Fibonacci number sequence, A060455.
4

%I #11 Jan 31 2021 20:50:36

%S 7,8,11,12,14,15,16,17,18,19,21,23,26,32,33,36,42,44,71,72,137,180,

%T 193,285,679,955,1018,1155,1176,1191,2149,2590,2757,3364,4233,6243,

%U 6364,7443,10194,11254,13318,18995,20478,22647,29711,34769,61815,71993,107494,135942,148831

%N Indices of primes in the 7th-order Fibonacci number sequence, A060455.

%C a(52) > 2*10^5.

%H Tony D. Noe and Jonathan Vos Post, <a href="http://www.cs.uwaterloo.ca/journals/JIS/VOL8/Noe/noe5.html">Primes in Fibonacci n-step and Lucas n-step Sequences</a>, J. of Integer Sequences, Vol. 8 (2005), Article 05.4.4

%t a={1,1,1,1,1,1,1}; step=7; lst={}; For[n=step,n<=1000,n++, sum=Plus@@a; If[PrimeQ[sum], AppendTo[lst,n]]; a=RotateLeft[a]; a[[7]]=sum]; lst

%Y Cf. A001590, A001631, A100683, A231574, A231575, A232542, A214899, A230607, A020992, A232498, A214727, A081172, A214752, A141523, A214825, A235862, A000288, A000322, A000383, A249413, A060455.

%K nonn

%O 1,1

%A _Robert Price_, Dec 30 2014