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%I #16 Apr 08 2023 16:03:12
%S 1,6,28,140,728,1638,2184,3640,8008,8190,10920,18620,23808,23895,
%T 27846,37128,47790,55860,69160,148960,166656,189810,237510,242060,
%U 316680,334530,359600,406215,446880,484120,525690,669060,726180,1029952,1078800,1089270,1099170
%N (1+e)-harmonic numbers: harmonic mean of (1+e)-divisors is an integer.
%C If k = Product p(i)^r(i), d = Product p(i)^s(i) and s(i) = 0 or s(i) divides r(i), then d is a (1+e)-divisor of k.
%H Amiram Eldar, <a href="/A053783/b053783.txt">Table of n, a(n) for n = 1..100</a>
%t f[p_, e_] := (DivisorSigma[0, e] + 1)/(p^e + DivisorSum[e, p^(e - #) &]); aQ[n_] := IntegerQ[n * Times @@ (f @@@ FactorInteger[n])]; Select[Range[10^5], aQ] (* _Amiram Eldar_, Sep 07 2019 *)
%Y Cf. A001599, A049599, A051378, A053784.
%K nonn
%O 1,2
%A _Naohiro Nomoto_, Apr 14 2001
%E More terms from _Amiram Eldar_, Sep 07 2019
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