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A058025 Numbers k such that 3*13^k - 2 is prime. 1
1, 5, 11, 16, 59, 239, 299, 2524, 2695, 7657, 14028 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The next terms are > 15000. - Jinyuan Wang, Feb 02 2020

LINKS

Table of n, a(n) for n=1..11.

EXAMPLE

3(13^5) - 2 = 1113877, which is a prime number, hence 5 is in the sequence.

3(13^7) - 2 = 188245549, but that is divisible by 211, hence 7 is NOT in the sequence.

MATHEMATICA

Do[ If[ PrimeQ[ 3*13^n - 2 ], Print[ n ] ], {n, 0, 1500} ] (* RGWv *)

Select[Range[0, 4000], PrimeQ[(3*13^# - 2)] &] (* Vincenzo Librandi, Sep 28 2012 *)

PROG

(PARI) is(n)=ispseudoprime(3*13^n-2) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Cf. A057871 (3*13^k + 2 is prime).

Sequence in context: A041046 A041117 A041491 * A042121 A123082 A084037

Adjacent sequences:  A058022 A058023 A058024 * A058026 A058027 A058028

KEYWORD

nonn,more

AUTHOR

Robert G. Wilson v, Nov 15 2000

EXTENSIONS

a(8)-a(9) from Vincenzo Librandi, Sep 28 2012

a(10) from Bruno Berselli, Sep 28 2012

a(11) from Jinyuan Wang, Feb 02 2020

STATUS

approved

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Last modified June 14 09:06 EDT 2021. Contains 345018 sequences. (Running on oeis4.)