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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A353617 Decimal expansion of the asymptotic median of the abundancy indices of the positive integers.

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%I A353617 #10 May 01 2022 07:56:29
%S A353617 1,5,2,3,8,1
%N A353617 Decimal expansion of the asymptotic median of the abundancy indices of the positive integers.
%C A353617 The abundancy index of a number k is sigma(k)/k = A017665(k)/A017666(k), where sigma is the sum-of-divisors function (A000203).
%C A353617 Davenport (1933) proved that sigma(k)/k possesses a continuous distribution function. Therefore, it has an asymptotic median.
%C A353617 The asymptotic mean of the abundancy indices is Pi^2/6 = 1.64493... (A013661).
%C A353617 Mitsuo Kobayashi (unpublished, 2018) found that the median is in the interval (1.523812, 1.5238175) (see the MathOverflow link).
%D A353617 Harold Davenport, Über numeri abundantes, Sitzungsberichte der Preußischen Akademie der Wissenschaften, phys.-math. Klasse, No. 6 (1933), pp. 830-837.
%H A353617 Sébastien Palcoux, <a href="https://mathoverflow.net/questions/364542/on-the-density-map-of-the-abundancy-index">On the density map of the abundancy index</a>, MathOverflow, 2020.
%e A353617 1.52381...
%Y A353617 Cf. A000203, A013661, A017665, A017666, A302991, A353615, A353616.
%K A353617 nonn,cons,more
%O A353617 1,2
%A A353617 _Amiram Eldar_, Apr 30 2022