

A348697


Numbers m such that there is at least two smaller numbers k < m with the same harmonic mean of divisors as m.


1



321048, 448335, 1284192, 1605240, 1672125, 1862190, 3531528, 5016375, 5457816, 6420960, 7384104, 7621695, 8026200, 9310392, 9952488, 10311705, 11878776, 13001715, 13035330, 13162968, 13805064, 13898385, 14126112, 15089256, 16588395, 17015544, 17657640, 17836000
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OFFSET

1,1


COMMENTS

What is the least term m with more than two smaller numbers k with the same harmonic mean of divisors as m?


LINKS



EXAMPLE

321048 is a term since the harmonic mean of divisors of 321048 is 3528/125, and it is also the harmonic mean of divisors of both 201096 and 296352 which are smaller than 321048.


MATHEMATICA

h = Table[DivisorSigma[0, n]/DivisorSigma[1, n], {n, 1, 2*10^6}]; i = Position[(t = Tally[h])[[;; , 2]], _?(# > 2 &)] // Flatten; Position[h, #][[3 ;; 1]] & /@ t[[i, 1]] // Flatten // Sort


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



