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%I #33 Aug 12 2019 02:23:49
%S 5,11,7,23,33,11,47,79,15,73,95,171,67,129,177,23,191,355,309,27,315,
%T 385,283,289,383,723,35,739,393,39,687,801,489,1089,711,767,47,1459,
%U 649,281,1599,969,801,607,1431,1633,59,1971,2581,63,1555,1535,1153,1069,2931,1605,927,1843,3319,2121
%N Odd values of sigma(n) - phi(n) in the order of appearance and with repetition.
%C Odd values of A051612(n) sorted along n.
%H Robert Israel, <a href="/A226586/b226586.txt">Table of n, a(n) for n = 1..10000</a>
%F sigma(4) - phi(4) = 7 - 2 = 5. Since 5 is the first odd value of sigma(n) - phi(n), it appears first in the list. So a(1) = 5.
%p select(type, [seq(numtheory:-sigma(n)-numtheory:-phi(n), n=1..2000)], odd); # _Robert Israel_, Aug 11 2019
%t Select[Table[DivisorSigma[1,n]-EulerPhi[n],{n,2000}],OddQ] (* _Harvey P. Dale_, Sep 27 2013 *)
%Y Cf. A051612, A028982.
%K nonn
%O 1,1
%A _Wesley Ivan Hurt_, Jun 28 2013