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A253705
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Indices of primes in the 8th-order Fibonacci number sequence, A079262.
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3
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OFFSET
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1,1
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COMMENTS
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a(9) > 2*10^5.
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LINKS
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MATHEMATICA
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a={0, 0, 0, 0, 0, 0, 0, 1}; step=8; lst={}; For[n=step, n<=1000, n++, sum=Plus@@a; If[PrimeQ[sum], AppendTo[lst, n]]; a=RotateLeft[a]; a[[step]]=sum]; lst
Flatten[Position[LinearRecurrence[{1, 1, 1, 1, 1, 1, 1, 1}, {0, 0, 0, 0, 0, 0, 0, 1}, 200000], _?PrimeQ]]-1 (* The program takes a long time to run *) (* Harvey P. Dale, Apr 26 2018 *)
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PROG
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(PARI) lista(nn) = {gf = x^7/(1-x-x^2-x^3-x^4-x^5-x^6-x^7-x^8); for (n=0, nn, if (isprime(polcoeff(gf+O(x^(n+1)), n)), print1(n, ", ")); ); } \\ Michel Marcus, Jan 12 2015
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CROSSREFS
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Cf. A001590, A001631, A100683, A231574, A231575, A232542, A214899, A230607, A020992, A232498, A214727, A081172, A214752, A141523, A214825, A235862, A000288, A000322, A000383, A249413, A060455, A079262.
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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