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A274239 Numbers n such that 9^n + 8^(n+1) is prime. 0
1, 2, 5, 20, 53, 161, 380, 500, 530, 698, 832, 833, 6353, 25433, 53921, 73538 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(17) > 10^5.

LINKS

Table of n, a(n) for n=1..16.

MATHEMATICA

Select[Range[0, 100000], PrimeQ[9^# + 8^(# + 1)] &]

PROG

(Magma) [n: n in [0..500] | IsPrime(9^n+8^(n+1))]; // Vincenzo Librandi, Jul 12 2016

(PARI) is(n)=ispseudoprime(9^n+8^(n+1)) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Cf. A093765.

Sequence in context: A098510 A168541 A124264 * A271858 A189734 A221678

Adjacent sequences: A274236 A274237 A274238 * A274240 A274241 A274242

KEYWORD

nonn,more

AUTHOR

Robert Price, Jun 15 2016

STATUS

approved

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Last modified February 7 09:08 EST 2023. Contains 360115 sequences. (Running on oeis4.)