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%I #13 Apr 24 2022 06:36:35
%S 2,4,6,10,16,28,78,114,152,165,186,222,224,238,256,402,496,654,704,
%T 738,762,834,942,1086,1194,1266,1456,1485,1665,1722,1842,1972,2022,
%U 2132,2223,2274,2454,2528,2754,2922,2994,3246,3426,3462,3472,3786,4506,4614
%N Numbers k such that phi(k) = phi(sigma(k)-k).
%H Amiram Eldar, <a href="/A067880/b067880.txt">Table of n, a(n) for n = 1..10000</a>
%t Select[Range[5000], EulerPhi[#] == EulerPhi[DivisorSigma[1, #] - #] &] (* _Amiram Eldar_, Apr 24 2022 *)
%Y Cf. A000010, A000203, A001065, A006872.
%K easy,nonn
%O 1,1
%A _Benoit Cloitre_, Mar 02 2002