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 A128163 Numbers k such that A128162(k) is prime. 2
 5, 7, 9, 11, 13, 14, 15, 26, 30, 53, 66, 82, 155, 189, 225, 261, 625, 870, 1071, 7655, 8191, 8883, 9226, 12246, 70274, 71595 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Corresponding primes in A128162 are {3, 3, 31, 37, 137, 347, 487, 77951, 166409, 13506083561, ...}. LINKS MATHEMATICA Do[f=PowerMod[3, n, Fibonacci[n]]; If[PrimeQ[f], Print[{n, f}]], {n, 1, 1071}] Select[Range[72000], PrimeQ[PowerMod[3, #, Fibonacci[#]]]&] (* Harvey P. Dale, Sep 11 2019 *) PROG (PARI) is(n)=ispseudoprime(3^n%fibonacci(n)) \\ Charles R Greathouse IV, Jun 19 2017 (PFGW) ABC2 3^\$a % F(\$a) a: from 5 to 1000000 // Charles R Greathouse IV, Jun 19 2017 CROSSREFS Cf. A128162 (3^n modulo Fibonacci(n)), A128161, A057862 (2^n modulo Fibonacci(n)). Sequence in context: A175382 A279244 A325797 * A177088 A168146 A343064 Adjacent sequences:  A128160 A128161 A128162 * A128164 A128165 A128166 KEYWORD hard,more,nonn AUTHOR Alexander Adamchuk, Feb 19 2007 EXTENSIONS Corrected and extended by Stefan Steinerberger, Jun 10 2007 a(25)-a(26) from Donovan Johnson, Sep 03 2008 STATUS approved

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Last modified May 20 01:04 EDT 2022. Contains 353847 sequences. (Running on oeis4.)