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A128450 Numbers n such that absolute value of 10^n - n^10 is prime. 9
3, 9, 273, 399 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

MATHEMATICA

lst={}; k=10; Do[If[PrimeQ[Abs[k^n-n^k]], AppendTo[lst, n]], {n, 0, 10^4}]; lst (* Vladimir Joseph Stephan Orlovsky, Sep 10 2008 *)

Select[Range[0, 10000], PrimeQ[10^# - #^10] &] (* Vincenzo Librandi, Apr 01 2015 *)

PROG

(MAGMA) [n: n in [0..500]| IsPrime(10^n-n^10)]; // Vincenzo Librandi, Apr 01 2015

(PARI) is(n)=isprime(abs(10^n-n^10)) \\ Charles R Greathouse IV, Feb 17 2017

CROSSREFS

Cf. A072180, A109387, A117705, A117706, A128447, A128448, A128449, A128451, A122003, A128453, A128454.

Sequence in context: A318970 A132516 A328125 * A132562 A303130 A144984

Adjacent sequences:  A128447 A128448 A128449 * A128451 A128452 A128453

KEYWORD

hard,more,nonn,less

AUTHOR

Alexander Adamchuk, Mar 03 2007

STATUS

approved

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Last modified September 20 19:48 EDT 2020. Contains 337265 sequences. (Running on oeis4.)