

A053784


Harmonic means of (1+e)divisors of (1+e)harmonic numbers.


3



1, 2, 3, 5, 6, 9, 9, 10, 11, 15, 15, 14, 8, 9, 17, 17, 12, 21, 19, 16, 14, 18, 29, 26, 29, 21, 20, 17, 24, 28, 22, 27, 39, 24, 30, 42, 23, 42, 48, 33, 26, 54, 41, 35, 37, 36, 34, 39, 31, 44, 40, 36, 38, 46, 51, 55, 77, 41, 60, 77, 54, 57, 88, 47, 43, 45, 46, 99
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OFFSET

1,2


COMMENTS

If n = 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 n.


LINKS

Amiram Eldar, Table of n, a(n) for n = 1..100


MATHEMATICA

f[p_, e_] := (DivisorSigma[0, e] + 1)/(p^e + DivisorSum[e, p^(e  #) &]); h[n_] := n*Times @@ (f @@@ FactorInteger[n]); Select[h /@ Range[10^5], IntegerQ] (* Amiram Eldar, Sep 07 2019*)


CROSSREFS

Cf. A049599, A051378.
Sequence in context: A118809 A121048 A075389 * A036697 A131292 A276476
Adjacent sequences: A053781 A053782 A053783 * A053785 A053786 A053787


KEYWORD

nonn


AUTHOR

Naohiro Nomoto, Apr 14 2001


EXTENSIONS

More terms from Amiram Eldar, Sep 07 2019


STATUS

approved



