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A373987 Denominator of A373158(n) / A108951(n), where A108951 is fully multiplicative and A373158 is fully additive with a(p) = p# for prime p, where x# is the primorial A034386(x).

%I A373987 #9 Jun 25 2024 23:43:44
%S A373987 1,1,1,1,1,3,1,4,3,15,1,12,1,105,5,2,1,36,1,60,35,1155,1,4,15,15015,
%T A373987 12,420,1,180,1,16,1155,255255,105,9,1,4849845,15015,20,1,1260,1,4620,
%U A373987 180,111546435,1,48,105,900,85085,60060,1,108,385,70,1616615,3234846615,1,18,1,100280245065,1260,16,5005,13860,1,1021020
%N A373987 Denominator of A373158(n) / A108951(n), where A108951 is fully multiplicative and A373158 is fully additive with a(p) = p# for prime p, where x# is the primorial A034386(x).
%H A373987 Antti Karttunen, <a href="/A373987/b373987.txt">Table of n, a(n) for n = 1..4096</a>
%H A373987 <a href="/index/Pri#primorial_numbers">Index entries for sequences related to primorial numbers</a>
%F A373987 a(n) = A108951(n) / A373985(n) = A108951(n) / gcd(A108951(n), A373158(n)).
%o A373987 (PARI) A373987(n) = { my(f=factor(n),m=1,s=0); for(i=1, #f~, my(x=prod(i=1,primepi(f[i, 1]),prime(i))); s += f[i, 2]*x; m *= x^f[i, 2]); m/gcd(m,s); };
%o A373987 (PARI) A373987(n) = denominator(A373158(n)/A108951(n));
%Y A373987 Cf. A108951, A373158, A373985, A373986 (numerators).
%K A373987 nonn,frac
%O A373987 1,6
%A A373987 _Antti Karttunen_, Jun 25 2024