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A157849 Numbers k such that are not harmonic means of divisors of harmonic (Ore) numbers (harmonic (Ore) numbers is A001599). 1

%I #19 Feb 22 2020 20:50:02

%S 4,12,16,18,20,22,23,28,30,32,33,34,36,38,40,43,52,55,56,57,58,59,62,

%T 63,64,65,66,67,68,69,71,72,74,76,79,90,93,95,98,100,103,104,109,111,

%U 112,113,119,122,123,124,126,129,131,133,134,136,137,138,141,142,146,148,151,154,157,162,170

%N Numbers k such that are not harmonic means of divisors of harmonic (Ore) numbers (harmonic (Ore) numbers is A001599).

%C a(n) non-occurring in A001600(m) = A001599(m)*tau(A001599(m))/sigma(A001599(m)) = A001599(m)*A000005(A001599(m))/A000203(A001599(m)).

%H Robert G. Wilson v, <a href="/A157849/b157849.txt">Table of n, a(n) for n = 1..412</a>

%H Takeshi Goto, <a href="http://www.ma.noda.tus.ac.jp/u/tg/files/uts.pdf">On Ore's harmonic numbers</a>, slides, Tokyo University of Science, Japan.

%Y Cf. A001600, A001599, A000005, A000203.

%K nonn

%O 1,1

%A _Jaroslav Krizek_, Mar 07 2009

%E More terms from _Robert G. Wilson v_, Aug 18 2013

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