cp's OEIS Frontend

A336848 a(n) = A003973(n) / A336846(n).

%I A336848 #11 Aug 06 2020 23:28:15
%S A336848 1,2,3,13,4,2,6,10,31,8,7,13,9,4,12,121,10,62,12,52,18,14,15,2,19,6,
%T A336848 39,26,16,8,19,182,21,20,24,403,21,8,27,40,22,12,24,7,124,10,27,121,
%U A336848 133,38,6,13,30,26,4,20,36,32,31,52,34,38,62,1093,36,14,36,130,9,16,37,62,40,14,57,52,42,18,42,484,781
%N A336848 a(n) = A003973(n) / A336846(n).
%C A336848 If there are no more 1's in this sequence after the initial one, then there are no odd terms of A001599 (Ore's Harmonic Numbers) larger than one.
%H A336848 Antti Karttunen, <a href="/A336848/b336848.txt">Table of n, a(n) for n = 1..16383</a>
%H A336848 Antti Karttunen, <a href="/A336848/a336848.txt">Data supplement: n, a(n) computed for n = 1..65537</a>
%H A336848 <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>
%H A336848 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F A336848 a(n) = A003973(n) / A336846(n).
%o A336848 (PARI)
%o A336848 A003961(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
%o A336848 A336848(n) = { my(u=A003961(n),s=sigma(u)); (s/gcd(s, numdiv(n)*u)); };
%Y A336848 Cf. A000005, A000203, A001599, A003961, A003973, A336845, A336846, A336847, A336849.
%K A336848 nonn
%O A336848 1,2
%A A336848 _Antti Karttunen_, Aug 06 2020