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 A383297 #6 May 15 2025 08:22:11
%S A383297 3,5,9,11,15,17,23,27,29,33,41,43,53,57,59,63,65,71,75,79,83,85,87,89,
%T A383297 99,101,105,113,115,119,123,125,127,129,135,137,141,143,147,149,161,
%U A383297 169,173,179,187,195,197,203,207,209,221,225,229,235,239,249,251,253,257,259,261,267,281,287,293,295,297,311,313
%N A383297 Numbers k for which A276086(A006530(k-1)) divides A276086(k), where A006530 gives the largest prime factor of k, and A276086 is the primorial base exp-function.
%H A383297 Antti Karttunen, <a href="/A383297/b383297.txt">Table of n, a(n) for n = 1..10000</a>
%H A383297 <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>.
%o A383297 (PARI)
%o A383297 A006530(n) = if(1==n, n, my(f=factor(n)); f[#f~, 1]);
%o A383297 A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
%o A383297 isA383297(n) = ((n>1) && !(A276086(n)%A276086(A006530(n-1))));
%Y A383297 Cf. A006530, A276086, A383296 (subsequence).
%K A383297 nonn
%O A383297 1,1
%A A383297 _Antti Karttunen_, May 15 2025