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%I #15 Apr 01 2018 10:46:26
%S 1,84,204,294,364,440,444,564,600,644,804,884,950,1000,1134,1164,1204,
%T 1240,1274,1284,1320,1344,1350,1400,1450,1484,1524,1564,1640,1644,
%U 1734,1884,1900,1924,2004,2044,2090,2200,2254,2324,2364,2440,2444,2600,2700,2724
%N n, phi(n) and sigma(n) end with the same digit.
%F It seems that lim n -> infinity a(n)/n exists around 40.
%t Select[Range[3000],Last[IntegerDigits[#]]==Last[ IntegerDigits[ EulerPhi[ #]]] == Last[ IntegerDigits[ DivisorSigma[1,#]]]&] (* _Harvey P. Dale_, Aug 03 2014 *)
%o (PARI) isok(n) = ((n % 10) == (eulerphi(n) % 10)) && ((n % 10) == (sigma(n) % 10)); \\ _Michel Marcus_, Nov 26 2013
%Y Intersection of A072566 and A072585.
%Y Cf. A000010, A000203.
%K base,nonn
%O 1,2
%A _Benoit Cloitre_, Aug 06 2002
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