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A056800 Numbers n such that 6*9^n +1 is prime. 1
0, 2, 4, 8, 28, 32, 448, 2108, 3112, 76264 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(11) > 10^5. - Robert Price, Jun 04 2015

LINKS

Table of n, a(n) for n=1..10.

MATHEMATICA

Do[If[PrimeQ[6*9^n + 1], Print[n]], {n, 0, 1000}]

Select[Range[3000], PrimeQ[6 9^# + 1] &] (* Vincenzo Librandi, Sep 28 2012 *)

PROG

(PARI) is(n)=ispseudoprime(6*9^n+1) \\ Charles R Greathouse IV, Jun 12 2017

CROSSREFS

Sequence in context: A006399 A326293 A324328 * A302915 A259135 A219969

Adjacent sequences:  A056797 A056798 A056799 * A056801 A056802 A056803

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Aug 22 2000

EXTENSIONS

a(8) from Vincenzo Librandi, Sep 28 2012

a(9)-a(10) from Robert Price, Jun 04 2015

STATUS

approved

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Last modified October 2 01:30 EDT 2022. Contains 357191 sequences. (Running on oeis4.)