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Indices of primes in the 9th-order Fibonacci number sequence, A104144.
1

%I #7 Mar 10 2015 01:42:51

%S 10,19,878

%N Indices of primes in the 9th-order Fibonacci number sequence, A104144.

%C a(4) > 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={0,0,0,0,0,0,0,0,1}; step=9; lst={}; For[n=step,n<=1000,n++, sum=Plus@@a; If[PrimeQ[sum], AppendTo[lst,n]]; a=RotateLeft[a]; a[[step]]=sum]; lst

%o (PARI) a104144(n) = polcoeff(x^8/(1-x-x^2-x^3-x^4-x^5-x^6-x^7-x^8-x^9) + O(x^(n+1)), n);

%o lista(nn) = {for (n=1, nn, if (isprime(a104144(n)), print1(n, ", ")););} \\ _Michel Marcus_, Feb 27 2015

%Y Cf. A001590, A001631, A100683, A231574, A231575, A232542, A214899, A230607, A020992, A232498, A214727, A081172, A214752, A141523, A214825, A235862, A000288, A000322, A000383, A249413, A060455, A079262, A104144.

%K nonn,more

%O 1,1

%A _Robert Price_, Feb 24 2015