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A228145 Numbers n such that 2*Fibonacci(n) - 1 is prime. 2
3, 4, 8, 9, 10, 16, 18, 31, 34, 39, 41, 42, 55, 68, 79, 90, 95, 97, 114, 122, 148, 151, 160, 209, 265, 320, 329, 441, 457, 516, 529, 632, 640, 682, 712, 791, 1056, 1169, 1632, 1943, 2200, 2279, 2468, 2698, 2921, 2996, 3129, 3140, 3656, 3960, 4889, 5560, 5895 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..55

MATHEMATICA

Select[Range[2000], PrimeQ[2 Fibonacci[#] - 1]&]

PROG

(MAGMA) [n: n in [1..1700] | IsPrime(2*Fibonacci(n)-1)];

(PARI) is(n)=ispseudoprime(2*fibonacci(n)-1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Cf. A124067.

Sequence in context: A075746 A275096 A109826 * A243064 A057549 A284392

Adjacent sequences:  A228142 A228143 A228144 * A228146 A228147 A228148

KEYWORD

nonn

AUTHOR

Vincenzo Librandi, Aug 13 2013

STATUS

approved

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Last modified January 28 10:02 EST 2020. Contains 331319 sequences. (Running on oeis4.)