

A058025


Numbers k such that 3*13^k  2 is prime.


1



1, 5, 11, 16, 59, 239, 299, 2524, 2695, 7657, 14028
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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^n2) \\ 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



