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 A347250 #4 Aug 30 2021 09:38:33
%S A347250 9,17,18,34,36,49,67,68,71,72,81,97,98,134,136,142,144,147,162,193,
%T A347250 194,196,268,271,272,283,284,288,291,293,294,324,386,388,392,536,541,
%U A347250 542,544,566,568,576,579,582,586,587,588,647,648,679,772,776,784,961,1072,1082,1084,1087,1088,1132,1136,1151,1152,1158,1163
%N A347250 Numbers k for which A331410(k) < A336361(k).
%C A347250 If k is a term, then also 2*k is present in this sequence.
%o A347250 (PARI)
%o A347250 A331410(n) = { my(f=factor(n)); sum(k=1,#f~,if(2==f[k,1],0,f[k,2]*(1+A331410(f[k,1]+1)))); };
%o A347250 A336361(n) = if(!bitand(n,n-1),0,1+A336361(sigma(n>>valuation(n,2))));
%o A347250 A347249(n) = (A331410(n)-A336361(n));
%o A347250 isA347250(n) = (A347249(n)<0);
%Y A347250 Cf. A331410, A336361.
%Y A347250 Positions of negative terms in A347249.
%K A347250 nonn
%O A347250 1,1
%A A347250 _Antti Karttunen_, Aug 28 2021