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 A379494 #6 Jan 05 2025 13:36:54
%S A379494 3,4,10,12,34,5,18,20,51,75,178,-175,98,105,270,300,898,-500,498,-375,
%T A379494 1410,2175,4498,1215,2495,3525,7450,5625,22498,-161,26,28,-66,-249,
%U A379494 202,-8680,138,-915,-30,-1995,1258,-4025,698,735,2058,1275,6298,-9275,3485,4900,9750,14175,31498,8505,17050,25809,50250,78729
%N A379494 a(n) = 2*A276086(n) - A276086(A001065(n)), where A276086 is the primorial base exp-function, and A001065 is the sum of proper divisors of n.
%H A379494 Antti Karttunen, <a href="/A379494/b379494.txt">Table of n, a(n) for n = 1..30030</a>
%H A379494 <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>.
%H A379494 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>.
%F A379494 a(n) = 2*A276086(n) - A379493(n).
%o A379494 (PARI)
%o A379494 A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
%o A379494 A379494(n) = (2*A276086(n) - A276086(sigma(n)-n));
%Y A379494 Cf. A001065, A276086, A379493.
%K A379494 sign
%O A379494 1,1
%A A379494 _Antti Karttunen_, Jan 05 2025