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A217133 Numbers n such that 5^n + 8 is prime. 1
1, 95, 335, 3155, 28651, 91135 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Naturally these numbers are odd since (6-1)^(2n)+8 is divisible by 3. - Bruno Berselli, Oct 04 2012
a(7) > 10^5. - Robert Price, Feb 03 2014
a(7) > 5*10^5. - Tyler NeSmith, Apr 24 2022
LINKS
MATHEMATICA
Select[Range[1, 15000, 2], PrimeQ[5^# + 8] &]
PROG
(PARI) for(n=1, 5*10^3, if(isprime(5^n+8), print1(n", ")))
CROSSREFS
Sequence in context: A008875 A174157 A200882 * A055823 A116250 A362322
KEYWORD
nonn,more
AUTHOR
Vincenzo Librandi, Oct 01 2012
EXTENSIONS
a(5)-a(6) from Robert Price, Feb 03 2014
STATUS
approved

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Last modified June 20 23:53 EDT 2024. Contains 373535 sequences. (Running on oeis4.)