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 A359566 #10 Jan 09 2023 01:23:57 %S A359566 12,40,126,364,544,546,1026,1100,1170,1650,2812,3591,3608,4095,4100, %T A359566 4214,4218,4510,6138,6150,7564,8658,9394,9548,9990,10804,10850,11096, %U A359566 11132,11346,11368,12078,13286,13870,13950,14210,14322,16206,16376,16698,17082,17290 %N A359566 Primitive terms of A359565: terms of A359565 with no proper divisor in A359565. %C A359566 If k is a term then all the positive multiples of k are terms of A359565. %H A359566 Amiram Eldar, <a href="/A359566/b359566.txt">Table of n, a(n) for n = 1..10000</a> %t A359566 q[n_] := Max[Tally[EulerPhi[Divisors[n]]][[;; , 2]]] > 2; primQ[n_] := q[n] && AllTrue[Divisors[n], # == n || !q[#] &]; Select[Range[17000], primQ] %o A359566 (PARI) is1(k) = vecmax(matreduce(apply(x->eulerphi(x), divisors(k)))[,2]) > 2; %o A359566 is(k) = fordiv(k, d, if(is1(d), return(d==k))); return(0); %Y A359566 Cf. A326835, A359563, A359564, A359565. %K A359566 nonn %O A359566 1,1 %A A359566 _Amiram Eldar_, Jan 06 2023