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 A370115 #14 Feb 11 2024 14:20:04
%S A370115 0,1,2,10,15,161,2189,5005,27030,29861,510221,223092341
%N A370115 Numbers k for which k is a multiple of A276086(A003415(k)), where A003415 is the arithmetic derivative, and A276086 is the primorial base exp-function.
%C A370115 Question: Is the squarefreeness a necessary condition for the nonzero terms of this sequence?
%C A370115 Many of the terms occur also in A368703, because the arithmetic derivative of those terms is one of the primorial numbers, A002110.
%C A370115 If it exists, a(13) > 1241513984.
%o A370115 (PARI)
%o A370115 A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
%o A370115 A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
%o A370115 isA370115(n) = !(n%A276086(A003415(n)));
%Y A370115 Positions of 1's in A370117, positions of 0's in A370120.
%Y A370115 Intersection of A048103 and A369650 is a subsequence of this sequence. See the comments in latter.
%Y A370115 Cf. A002110, A003415, A276086, A327859, A368703.
%Y A370115 Cf. also A369970, A370114.
%K A370115 nonn
%O A370115 1,3
%A A370115 _Antti Karttunen_, Feb 11 2024