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%I A337385 #11 Sep 25 2020 04:23:27
%S A337385 334639305,1003917915,1265809545,1353106755,1673196525,2109682575,
%T A337385 2255177925,2342475135,2553826275,2691663975,2729952225,2953555605,
%U A337385 2982654675,3011753745,3128150025,3157249095,3234846615,3258330075,3419140725,3442113675,3681032355,3797428635,3855626775,4059320265,4292112825,4350310965
%N A337385 Odd numbers k for which A003973(k) >= 2*A003961(k).
%C A337385 Provided that there are no odd perfect numbers, then applying A003961 to each term and sorting into ascending order gives A115414.
%C A337385 Apparently, all terms are divisible by 255255 = 3*5*7*11*13*17. - _Hugo Pfoertner_, Sep 24 2020
%H A337385 <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>
%H A337385 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%o A337385 (PARI)
%o A337385 A003961(n) = { my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
%o A337385 isA337385(n) = if(!(n%2),0,my(x=A003961(n)); (sigma(x)>=2*x));
%Y A337385 Subsequence of A337386.
%Y A337385 Cf. A000203, A003961, A003973, A115414.
%K A337385 nonn
%O A337385 1,1
%A A337385 _Antti Karttunen_, Aug 31 2020

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