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Numbers n such that 13*n + 3 is not prime.
2

%I #13 Sep 08 2022 08:45:41

%S 1,3,4,5,6,7,9,10,11,12,13,14,15,17,18,19,21,22,23,24,25,26,27,29,30,

%T 31,33,34,35,36,37,38,39,41,42,43,44,45,47,48,49,51,52,53,54,55,56,57,

%U 59,60,61,63,64,65,66,67,69,70,71,72,73,74,75,77,78,79,80,81,83,84,85,86,87

%N Numbers n such that 13*n + 3 is not prime.

%H Vincenzo Librandi, <a href="/A155854/b155854.txt">Table of n, a(n) for n = 1..1000</a>

%t Select[Range[100], !PrimeQ[13 # + 3] &]

%o (Magma) [n: n in [0..90] | not IsPrime(13*n + 3)]; // _Vincenzo Librandi_, Oct 15 2012

%Y Cf. A100202, A155853.

%K nonn,easy

%O 1,2

%A _Vincenzo Librandi_, Jan 29 2009

%E Data corrected by Harvey P. Dale, Sep 11 2011