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.
%I A138685 #16 May 17 2024 09:55:57
%S A138685 13,28,34,43,55,58,67,73,76,88,97,100,103,106,118,133,139,145,148,157,
%T A138685 160,163,166,178,181,184,193,199,202,208,214,223,232,238,244,253,259,
%U A138685 262,265,268,271,283,286,298,301,307,310,313,328,331,340,343,349,352
%N A138685 Numbers k such that there is no prime of the form 2k + p^2 for any prime p.
%C A138685 Indices where zero occurs in A138479.
%C A138685 For primes in this sequences see A138686.
%H A138685 Alois P. Heinz, <a href="/A138685/b138685.txt">Table of n, a(n) for n = 1..10000</a>
%F A138685 Based on comments from _Zak Seidov_, _Don Reble_ and _M. F. Hasler_, we now know that these are the numbers k such that k == 1 (mod 3) and 2k + 9 is composite. - _N. J. A. Sloane_, Apr 20 2008
%t A138685 a = {}; Do[p = 0; While[(! PrimeQ[2*n + Prime[p + 1]^2]) && (p < 10000), p++ ]; If[p < 10000,[null], AppendTo[a, n]], {n, 1, 550}]; a
%t A138685 Select[Range[400],Mod[#,3]==1&&CompositeQ[2#+9]&] (* _Harvey P. Dale_, Feb 23 2017 *)
%Y A138685 Cf. A138479, A138686.
%K A138685 nonn
%O A138685 1,1
%A A138685 _Artur Jasinski_, Mar 26 2008