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A348654 Indices of records in the sequence of unitary harmonic means A103339(k)/A103340(k).

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%I A348654 #17 Oct 28 2021 10:01:35
%S A348654 1,2,3,4,5,6,10,12,15,20,28,30,42,60,84,105,120,140,180,210,330,390,
%T A348654 420,660,780,840,1092,1155,1260,1540,1820,1980,2310,2730,3570,3990,
%U A348654 4290,4620,5460,7140,7980,8580,9240,10920,13860,16380,20020,23940,25740,27720,30030
%N A348654 Indices of records in the sequence of unitary harmonic means A103339(k)/A103340(k).
%H A348654 Amiram Eldar, <a href="/A348654/b348654.txt">Table of n, a(n) for n = 1..170</a>
%e A348654 The unitary harmonic means of the first 6 positive integers are 1 < 4/3 < 3/2 < 8/5 < 5/3 < 2. The next record, A103339(10)/A103340(10) = 20/9, occurs at 10. Therefore, the first 7 terms of this sequence are 1, 2, 3, 4, 5, 6 and 10.
%t A348654 f[p_, e_] := 2/(1 + p^(-e)); uhmeam[n_] := Times @@ f @@@ FactorInteger[n]; s = {}; max = 0; Do[u1 = uhmeam[n]; If[u1 > max, max = u1; AppendTo[s, n]], {n, 1, 10^5}]; s
%Y A348654 The unitary version of A179971.
%Y A348654 Cf. A103339, A103340.
%K A348654 nonn
%O A348654 1,2
%A A348654 _Amiram Eldar_, Oct 28 2021