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%I #36 Feb 04 2024 01:17:06
%S 0,1,2,4,5,7,10,11,14,16,17,19,20,25,26,31,32,34,37,40,41,44,47,49,52,
%T 55,56,59,62,65,67,70,76,77,82,86,89,91,94,95,104,107,109,110,115,116,
%U 119,121,122,124,125,130,136,140,142,146,149,151,154,157,160,161,164
%N Numbers k such that 4k + 3 is prime.
%H Iain Fox, <a href="/A095278/b095278.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = (A002145(n) - 3)/4.
%p A095278:=n->`if`(isprime(4*n+3), n, NULL): seq(A095278(n), n=0..300); # _Wesley Ivan Hurt_, Jun 29 2015
%t Select[Range[0,200], PrimeQ[4#+3]&] (* _Harvey P. Dale_, Aug 15 2013 *)
%o (Magma) [n: n in [0..1000]|IsPrime(4*n+3)] // _Vincenzo Librandi_, Nov 16 2010
%o (PARI) is(n)=isprime(4*n+3) \\ _Charles R Greathouse IV_, Jul 01 2013
%o (GAP) Filtered([1..170],n->IsPrime(4*n+3)); # _Muniru A Asiru_, Oct 29 2018
%Y Cf. A002145. Complement of A095277. Union of A095272 and A095273. Cf. also A005098.
%K nonn,easy
%O 1,3
%A _Antti Karttunen_, Jun 01 2004