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 A173967 #13 Apr 07 2025 16:15:37
%S A173967 29,43,67,69,77,115,171,173,187,189,237,245,267,283,285,291,317,355,
%T A173967 403,405,411,427,429,435,437,507,597,603,605,653,669,763,787,789,891,
%U A173967 893,907,963,1003,1029,1053,1075,1085,1107,1131,1245,1267,1269,1389,1395
%N A173967 Sums of two consecutive numbers that are nonsquare semiprimes.
%F A173967 a(n) = A263990(n) + A109288(n). - _Andrey Zabolotskiy_, Apr 07 2025
%e A173967 14=2*7; 15=3*5; 14+15=29,
%e A173967 21=3*7; 22=2*11; 21+22=43,..
%t A173967 f[n_]:=Last/@FactorInteger[n]=={1,1};lst={};Do[If[f[n],If[f[n+1],AppendTo[lst,2*n+1]]],{n,7!}];lst
%Y A173967 Cf. A173966, A173969, A006881, A263990, A109288.
%K A173967 nonn
%O A173967 1,1
%A A173967 _Vladimir Joseph Stephan Orlovsky_, Mar 03 2010
%E A173967 New name from _Andrey Zabolotskiy_, Apr 07 2025