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%I #9 Jun 08 2020 02:29:36
%S 1,2,4,91,272,20118,20712,33998,42818,61695,25274946,27194929,
%T 34883654,40406622,43176318,47350866,52680050,149736013,154957034,
%U 162929406,171560153,187012577,208015843,267361097,300087726,325189758,355153181,443360633,584803578,605883413
%N Numbers m such that the delta(m) = abs(h(m+1) - h(m)) is smaller than delta(k) for all k < m, where h(m) is the harmonic mean of the divisors of m.
%C Apparently, most of the terms m have h(m+1) > h(m) and numerator(delta(m)) = 1.
%C Can two consecutive numbers have the same harmonic mean of divisors? If yes, then this sequence is finite.
%H Amiram Eldar, <a href="/A335291/b335291.txt">Table of n, a(n) for n = 1..86</a>
%e The values of delta(k) for the first terms are 0.333..., 0.166..., 0.047..., 0.0357..., ...
%t h[n_] := n * DivisorSigma[0, n]/DivisorSigma[1, n]; dm = 1; h1 = h[1]; s = {}; Do[h2 = h[n]; d = Abs[h2 - h1]; If[d < dm, dm = d; AppendTo[s, n-1]]; h1 = h2, {n, 2, 10^5}]; s
%Y Cf. A000005, A000203, A099377, A099378.
%Y Cf. A238380, A335071.
%K nonn
%O 1,2
%A _Amiram Eldar_, May 30 2020
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