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A128453 Numbers k such that absolute value of 13^k - k^13 is prime. 8
6, 12, 38, 2540 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(5) > 10^5. - Robert Price, Apr 17 2019

LINKS

Table of n, a(n) for n=1..4.

MATHEMATICA

Do[If[PrimeQ[13^n - n^13], Print[n]], {n, 10^4}] (* Ryan Propper, Jul 01 2007 *)

PROG

(PARI) is(n)=ispseudoprime(abs(13^n-n^13)) \\ Charles R Greathouse IV, Feb 17 2017

CROSSREFS

Sequence in context: A096377 A026083 A215179 * A185616 A307181 A052747

Adjacent sequences:  A128450 A128451 A128452 * A128454 A128455 A128456

KEYWORD

hard,more,nonn,less

AUTHOR

Alexander Adamchuk, Mar 03 2007

EXTENSIONS

a(4) from Ryan Propper, Jul 01 2007

STATUS

approved

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Last modified September 20 19:32 EDT 2020. Contains 337265 sequences. (Running on oeis4.)