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A214413 - OEIS
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A214413 a(n) is the smallest m such that the irreducible fraction m/n is not an abundancy outlaw. 2

%I #22 Jan 27 2019 05:42:50

%S 1,3,4,7,6,13,8,15,13,19,12,29,14,25,26,31,18,41,20,47,32,37,24,65,31,

%T 43,40,57,30,73,32,63,50,55,48,91,38,61,56,93,42,97,44,85,82,73,48,

%U 125,57,93,74,99,54,121,72,125,80,91,60,169,62,97,104,127,84

%N a(n) is the smallest m such that the irreducible fraction m/n is not an abundancy outlaw.

%C The theorem on page 7 of Stanton and Holdener gives conditions for a rational to be an abundancy outlaw.

%C For a given n, these conditions have been checked by starting with m/n=sigma(n)/n and then increasing m until they fail.

%H Michel Marcus, <a href="/A214413/b214413.txt">Table of n, a(n) for n = 1..1000</a>

%H William G. Stanton and Judy A. Holdener, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL10/Holdener/holdener7.html">Abundancy "Outlaws" of the Form (sigma(N) + t)/N</a>, Journal of Integer Sequences , Vol 10 (2007) , Article 07.9.6.

%e a(3) = 4 because 4/3 is the abundancy index of 3, so 4/3 is not an abundancy outlaw.

%Y Smaller than or equal to A214409.

%K nonn

%O 1,2

%A _Michel Marcus_, Jul 22 2012

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