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 A250178 Numbers k such that Phi_22(k) is prime, where Phi is the cyclotomic polynomial. 19

%I

%S 2,6,12,13,23,24,26,35,62,69,91,105,147,160,163,183,185,193,229,232,

%T 233,236,248,262,269,280,294,303,315,330,376,394,426,430,440,464,469,

%U 491,492,508,537,625,629,647,653,666,752,772,775,786,788,832,840,852,854,855,859,905,922,972,993,998

%N Numbers k such that Phi_22(k) is prime, where Phi is the cyclotomic polynomial.

%C Numbers k such that (k^11+1)/(k+1) is a prime. - _Vincenzo Librandi_, May 21 2018

%H G. C. Greubel, <a href="/A250178/b250178.txt">Table of n, a(n) for n = 1..10000</a>

%t a250178[n_] := Select[Range[n], PrimeQ@Cyclotomic[22, #] &]; a250178[1000] (* _Michael De Vlieger_, Dec 25 2014 *)

%o (PARI) isok(n) = isprime(polcyclo(22, n)); \\ _Michel Marcus_, Sep 29 2015

%o (MAGMA) [n: n in [1..1000]| IsPrime((n^11+1) div (n+1))]; // _Vincenzo Librandi_, May 21 2018

%Y See A250177 for references.

%K nonn

%O 1,1

%A _Eric Chen_, Dec 24 2014

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Last modified September 18 04:22 EDT 2021. Contains 347508 sequences. (Running on oeis4.)