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%I #15 Sep 08 2022 08:46:04
%S 15,21,26,86,89,114,123,163,180,310,332,377,409,438,448,457,477,526,
%T 534,556,586,612,653,665,690,692,709,760,783,803,821,848,877,899,909,
%U 942,981,1041,1042,1043,1066,1068,1069,1106,1126,1139,1197,1310,1386,1476,1561
%N Numbers n such that (n^43-1)/(n-1) is prime.
%H Vincenzo Librandi, <a href="/A217078/b217078.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Range[2, 1600], PrimeQ[(#^43 - 1)/(# - 1)] &] (* _T. D. Noe_, Sep 26 2012 *)
%o (Magma) [n: n in [2..1600] |IsPrime((n^43 - 1) div (n - 1))]; // _Vincenzo Librandi_, Sep 28 2012
%o (PARI) is(n)=isprime((n^43-1)/(n-1)) \\ _Charles R Greathouse IV_, Feb 17 2017
%Y Cf. A002384, A049409, A100330, A162862, A217070-A217089.
%K nonn,easy
%O 1,1
%A _Tim Johannes Ohrtmann_, Sep 26 2012
%E More terms from _T. D. Noe_, Sep 26 2012