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%I #10 Feb 15 2023 14:02:09
%S 1,1,1,1,1,6,1,1,1,9,1,14,1,12,8,1,1,39,1,7,32,18,1,30,1,21,1,28,1,24,
%T 1,1,16,27,48,91,1,30,56,45,1,96,1,14,13,36,1,62,1,31,24,49,1,60,72,
%U 60,80,45,1,56,1,48,26,1,84,48,1,21,32,144,1,195,1,57,62,70,96,168,1,31,1,63,1,224,108,66,40,90
%N Denominator of ratio A332993(n) / sigma(n).
%C See comments in A348978.
%H Antti Karttunen, <a href="/A348979/b348979.txt">Table of n, a(n) for n = 1..16384</a>
%H <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F a(n) = A000203(n) / A348977(n) = A000203(n) / gcd(A000203(n), A332993(n)).
%t f[n_] := n/FactorInteger[n][[1, 1]]; g[1] = 1; g[n_] := g[n] = n + g[f[n]]; a[n_] := Denominator[g[n]/DivisorSigma[1, n]]; Array[a, 100] (* _Amiram Eldar_, Nov 06 2021 *)
%o (PARI)
%o A332993(n) = if(1==n,n,n + A332993(n/vecmin(factor(n)[,1])));
%o A348979(n) = { my(s=sigma(n)); (s/gcd(s, A332993(n))); };
%Y Cf. A000203, A332993, A333783, A348977, A348978 (numerators).
%Y Cf. also A348988, A348989.
%K nonn,frac
%O 1,6
%A _Antti Karttunen_, Nov 06 2021
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