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A369445 Numerator of sigma(n) / A276086(n), where A276086 is the primorial base exp-function.

%I A369445 #9 Jan 25 2024 15:29:14
%S A369445 1,1,2,7,1,12,4,1,13,2,2,28,7,8,4,31,1,39,2,14,16,4,4,12,31,14,4,56,1,
%T A369445 72,16,3,8,6,8,13,19,4,4,2,1,96,22,4,13,8,8,124,57,31,12,14,3,24,36,8,
%U A369445 8,2,2,24,31,32,52,127,2,144,34,6,16,16,4,39,37,38,62,4,16,24,8,62,121,2,2,32,54,44,4,4,1,234,8,8,64
%N A369445 Numerator of sigma(n) / A276086(n), where A276086 is the primorial base exp-function.
%H A369445 Antti Karttunen, <a href="/A369445/b369445.txt">Table of n, a(n) for n = 1..16384</a>
%H A369445 <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>
%H A369445 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F A369445 a(n) = A000203(n) / A324644(n).
%o A369445 (PARI)
%o A369445 A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
%o A369445 A369445(n) = { my(s=sigma(n)); (s/gcd(s,A276086(n))); };
%Y A369445 Cf. A000203, A276086, A324644, A369446 (denominators), A369261.
%K A369445 nonn,frac
%O A369445 1,3
%A A369445 _Antti Karttunen_, Jan 25 2024