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%I #13 Jun 11 2022 05:23:13
%S 5,6,13,15,33,68,117,156,168,222,259,265,313,522,644,665,750,986,1065,
%T 1153,1178,1328,1351,1377,1447,1750,1812,1824,1976,2392,2482,3672,
%U 3885,4185,4460,4528,5450,5812,5824,6610,6804,7256,7306,8496,8930,9310
%N Numbers k such that phi(k) divides (sigma(k+2) + sigma(k-2)).
%H Amiram Eldar, <a href="/A067245/b067245.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Range[3, 10^4], Divisible[Plus @@ DivisorSigma[1, # + {-2, 2}], EulerPhi[#]] &] (* _Amiram Eldar_, Jun 11 2022 *)
%Y Cf. A000010, A000203.
%K nonn
%O 1,1
%A _Benoit Cloitre_, Feb 20 2002
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