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A057871 Numbers k such that 3*13^k + 2 is prime. 1
0, 1, 2, 22, 25, 35, 49, 95, 105, 107, 302, 351, 1907, 3435, 5051, 6885 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

a(17) > 10000. - Jinyuan Wang, Feb 02 2020

LINKS

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

MATHEMATICA

Do[ If[ PrimeQ[ 3*13^n + 2 ], Print[ n ] ], {n, 0, 1500} ]

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. A058025 (3*13^k - 2 is prime).

Sequence in context: A022373 A111751 A037416 * A152243 A074160 A137074

Adjacent sequences:  A057868 A057869 A057870 * A057872 A057873 A057874

KEYWORD

nonn,more

AUTHOR

Robert G. Wilson v, Nov 15 2000

EXTENSIONS

a(13)-a(14) from Vincenzo Librandi, Sep 28 2012

a(15)-a(16) from Jinyuan Wang, Feb 02 2020

STATUS

approved

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Last modified September 30 05:03 EDT 2020. Contains 337435 sequences. (Running on oeis4.)