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 A276495 #12 Sep 08 2022 08:46:17 %S A276495 1,127,251,1657,1777,1973,3181,21893,31951,50839,67607,138977 %N A276495 Odd numbers not of the form p + 2^m with p prime and m >= 0 for which the smallest k in A067760 such that n + 2^k is prime increases. %C A276495 There exist de Polignac numbers n such that for all k >= 1 the numbers n + 2^k are composite. It is conjectured that 30666137 is the smallest such number. %C A276495 a(13) >= 453143. %o A276495 (Magma) lst:=[]; c:=0; for n in [1..31951 by 2] do m:=-1; repeat m+:=1; a:=n-2^m; until a lt 1 or IsPrime(a); if a lt 1 then k:=0; repeat k+:=1; b:=n+2^k; until IsPrime(b); if k gt c then Append(~lst, n); c:=k; end if; end if; end for; lst; %Y A276495 Cf. A006285, A067760, A263644. %Y A276495 A276496 gives the record values. %K A276495 nonn,hard,more %O A276495 1,2 %A A276495 _Arkadiusz Wesolowski_, Sep 05 2016