cp's OEIS Frontend

A369446 Denominator of sigma(n) / A276086(n), where A276086 is the primorial base exp-function.

%I A369446 #9 Jan 25 2024 16:39:10
%S A369446 2,1,3,9,3,5,5,1,30,5,15,25,25,25,25,225,25,125,25,125,375,125,375,
%T A369446 125,1250,625,375,5625,375,7,7,1,7,7,21,5,35,7,15,7,15,175,175,25,175,
%U A369446 175,525,875,1750,875,875,1125,875,875,4375,875,2625,875,2625,7,49,49,147,441,21,245,245,35,245,245,245,245,1225
%N A369446 Denominator of sigma(n) / A276086(n), where A276086 is the primorial base exp-function.
%H A369446 Antti Karttunen, <a href="/A369446/b369446.txt">Table of n, a(n) for n = 1..16384</a>
%H A369446 <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>
%H A369446 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F A369446 a(n) = A276086(n) / A324644(n).
%o A369446 (PARI)
%o A369446 A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
%o A369446 A369446(n) = { my(u=A276086(n)); (u/gcd(u,sigma(n))); };
%Y A369446 Cf. A000203, A276086, A324644, A369445 (numerators).
%K A369446 nonn,frac
%O A369446 1,1
%A A369446 _Antti Karttunen_, Jan 25 2024