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%I #8 May 16 2016 14:16:58
%S 6,10,14,22,26,34,38,46,58,62,74,82,86,94,99,106,118,122,134,142,146,
%T 158,166,168,178,187,194,202,206,214,218,226,254,262,274,278,298,302,
%U 314,326,334,346,358,362,382,386,394,398,422,446,454,458,466,478,482
%N (n - Phi(n)) | Sigma(n) for composite n.
%H Harvey P. Dale, <a href="/A055163/b055163.txt">Table of n, a(n) for n = 1..1000</a>
%t Do[ If[ !PrimeQ[ n ], If[ Mod[ DivisorSigma[ 1, n ], n-EulerPhi[ n ] ] == 0, Print[ n ] ], {n, 1, 500} ]
%t Select[Range[500],CompositeQ[#]&&Divisible[DivisorSigma[1,#],#-EulerPhi[ #]]&] (* _Harvey P. Dale_, May 16 2016 *)
%K easy,nonn
%O 1,1
%A _Robert G. Wilson v_, Jun 30 2000
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