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 A177214 #6 Feb 16 2021 02:11:42
%S A177214 634,694,1387,1942,3403,4714,5062,5269,5353,5617,6805,7495,8587,9427,
%T A177214 9847,10018,10123,10705,10942,11293,12139,13162,13798,14191,14989,
%U A177214 15406,17197,19735,20866,21439,22114,22585,24277,25009,25351,25399,26734
%N A177214 Numbers k that are the products of two distinct primes such that 2*k-1, 4*k-3, 8*k-7, 16*k-15 and 32*k-31 are also products of two distinct primes.
%e A177214 634 is a term since 634 = 2*317, 2*634 - 1 = 1267 = 7*181, 4*634 - 3 = 2533 = 17*149, 8*634 - 7 = 5065 = 5*1013, 16*634 = 10129 = 7*1447, and 32*634 = 20257 = 47*431.
%t A177214 f[n_]:=Last/@FactorInteger[n]=={1,1}; lst={};Do[If[f[n]&&f[2*n-1]&&f[4*n-3]&&f[8*n-7]&&f[16*n-15]&&f[32*n-31],AppendTo[lst,n]],{n,0,9!}];lst
%Y A177214 Cf. A006881, A177210, A177211, A177212, A177213.
%K A177214 nonn
%O A177214 1,1
%A A177214 _Vladimir Joseph Stephan Orlovsky_, May 04 2010