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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A243811 Numbers k such that 2*k+3 and 2*k+5 are both prime.

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%I A243811 #19 Mar 13 2025 09:59:59
%S A243811 0,1,4,7,13,19,28,34,49,52,67,73,88,94,97,112,118,133,139,154,172,208,
%T A243811 214,229,259,283,298,307,319,328,403,409,412,427,439,508,514,523,529,
%U A243811 544,574,613,637,643,649,658,712,724,739,742,802,808,832,847,859,892,934
%N A243811 Numbers k such that 2*k+3 and 2*k+5 are both prime.
%H A243811 Vincenzo Librandi, <a href="/A243811/b243811.txt">Table of n, a(n) for n = 1..1000</a>
%F A243811 a(n) = A040040(n)-2.
%t A243811 Select[Range[0, 1000], PrimeQ[2 # + 3] && PrimeQ[2 # + 5] &]
%o A243811 (Magma) [n: n in [0..1000] | IsPrime(2*n+3) and IsPrime(2*n+5)];
%Y A243811 Cf. A040040, A067076, A089038.
%K A243811 nonn,easy,less
%O A243811 1,3
%A A243811 _Vincenzo Librandi_, Jun 11 2014