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 A368697 #4 Jan 09 2024 16:56:31
%S A368697 11025,17325,27225,28665,29925,36225,37485,38025,40425,47025,48825,
%T A368697 49725,53361,56925,63525,63945,65025,69825,70785,74025,74529,76725,
%U A368697 81225,81585,84525,84825,88725,90405,92169,92565,92925,98325,105525,106425,108225,110925,111573,111825,113925,116325,116865,117117,119025,119925
%N A368697 Numbers that are divisible by the squares of two distinct primes and whose arithmetic derivative (A003415) is a squarefree number of the form 4k+2.
%o A368697 (PARI)
%o A368697 A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
%o A368697 A057521(n) = { my(f=factor(n)); prod(i=1, #f~, if(f[i, 2]>1, f[i, 1]^f[i, 2], 1)); };
%o A368697 isA368697(n) = if(omega(A057521(n))<2, 0, my(d=A003415(n)); ((2==(d%4))&&issquarefree(d)));
%Y A368697 Intersection of A036785 and A368696, i.e., of A036785, A327862 and A328393.
%Y A368697 Cf. A003415, A057521.
%K A368697 nonn
%O A368697 1,1
%A A368697 _Antti Karttunen_, Jan 09 2024