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A057464 Numbers k such that 10*13^k + 1 is prime. 0
0, 1, 4, 7, 8, 26, 33, 64, 116, 201, 1278, 1927, 2549, 4054, 5379, 5704, 6639 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

a(18) > 10^4. - Jinyuan Wang, Jan 31 2020

LINKS

Table of n, a(n) for n=1..17.

MATHEMATICA

Do[ If[ PrimeQ[ 10*13^n + 1 ], Print[ n ] ], {n, 0, 1000} ]

Select[Range[0, 4000], PrimeQ[(10*13^# + 1)] &] (* Vincenzo Librandi, Sep 28 2012 *)

PROG

(PARI) is(n)=ispseudoprime(10*13^n+1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Sequence in context: A225430 A295325 A239290 * A160629 A093105 A141669

Adjacent sequences:  A057461 A057462 A057463 * A057465 A057466 A057467

KEYWORD

nonn,more

AUTHOR

Robert G. Wilson v, Sep 08 2000

EXTENSIONS

a(11)-a(13) from Vincenzo Librandi, Sep 28 2012

a(14)-a(17) from Jinyuan Wang, Jan 31 2020

STATUS

approved

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Last modified February 26 07:46 EST 2020. Contains 332277 sequences. (Running on oeis4.)