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A105133 Numbers n such that 8n + 5 is prime.

%I A105133 #36 Feb 04 2024 01:19:31
%S A105133 0,1,3,4,6,7,12,13,18,19,21,22,24,28,33,34,36,39,43,46,48,49,52,57,63,
%T A105133 67,69,76,81,82,84,87,88,91,94,96,99,102,103,106,109,117,124,126,127,
%U A105133 132,133,136,138,139,147,151,153,154,159,162,171,172,178,181,186,193,199,201,202
%N A105133 Numbers n such that 8n + 5 is prime.
%H A105133 Vincenzo Librandi, <a href="/A105133/b105133.txt">Table of n, a(n) for n = 1..1000</a>
%F A105133 a(n) = (A007521(n)-5)/8. - _Zak Seidov_, Sep 08 2015
%p A105133 M:=500; f:=proc(n) local t1,t2; t1:=[]; for k from 0 to M do t2:=2^n*k+2^(n-1)+1; if isprime(t2) then t1:=[op(t1),k]; fi; od; t1; end; f(3);
%t A105133 Select[Range[0, 300], PrimeQ[8 # + 5]&] (* _Vincenzo Librandi_, Jan 07 2013 *)
%o A105133 (Magma) [n: n in [0..500] | IsPrime(8*n+5)];  // _Vincenzo Librandi_, Jan 07 2013
%o A105133 (PARI) is(n)=isprime(8*n+5) \\ _Charles R Greathouse IV_, Feb 17 2017
%Y A105133 Cf. A095278, A105134-A105140, A002145, A007521, A105126-A105132.
%K A105133 nonn,easy
%O A105133 1,3
%A A105133 _N. J. A. Sloane_, based on correspondence from _Marco Matosic_, Apr 11 2005