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Numbers n that minimize sigma(n) / (n^(1-delta) d(n)) for some delta > 0, where d = divisor count = A000005, sigma = divisor sum = A000203.
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%I #24 Aug 12 2022 19:27:54

%S 1,2,6,12,60,120,360,2520,5040,55440,720720,1441440,4324320,21621600,

%T 367567200,6983776800,13967553600,321253732800,2248776129600,

%U 65214507758400,195643523275200,6064949221531200,12129898443062400,448806242393308800,18401055938125660800

%N Numbers n that minimize sigma(n) / (n^(1-delta) d(n)) for some delta > 0, where d = divisor count = A000005, sigma = divisor sum = A000203.

%C These are the miserable average divisor numbers. Similar to superior highly composite numbers (A002201) or colossally abundant numbers (A004490).

%C a(2)..a(26) are also the first 25 terms of A002201.

%H William C. Jagy, <a href="/A263572/b263572.txt">Table of n, a(n) for n = 1..93</a>

%H Mathematics Stack Exchange, <a href="http://math.stackexchange.com/questions/605279/bounds-on-the-average-of-the-divisors-of-natural-numbers">Bounds on the average of the divisors of natural numbers</a>

%Y Cf. A000005, A000203, A002201, A004490.

%K nonn

%O 1,2

%A _William C. Jagy_, Oct 21 2015