%I #19 Feb 16 2022 11:19:32
%S 1,3,8,10,18,24,30
%N Numbers n such that phi(n) = d(n).
%C Duplicate of A020488. - _Peter Luschny_, Aug 26 2011
%D D. S. Mitrinovic et al., Handbook of Number Theory, Kluwer, p. 11.
%t Select[Range[500],EulerPhi[#]==DivisorSigma[0,#]&] (* _Harvey P. Dale_, Jun 18 2011 *)
%Y Cf. A000010, A000005, A063070.
%K dead
%O 1,2
%A _N. J. A. Sloane_, Jan 23 2003
%E Corrected by _Harvey P. Dale_, Jun 18 2011
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