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%I #24 Feb 29 2020 03:30:34
%S 1,6,10,14,22,26,34,38,46,58,62,74,82,86,94,106,118,122,134,142,146,
%T 158,166,178,194,202,206,214,218,226,254,262,274,278,298,302,314,326,
%U 334,346,358,362,382,386,390,394,398,422,446,454,458,466,478
%N Numbers k such that phi(k)+2 divides k+2.
%C Consists of the even semiprimes (other than 4) together with A207575. - _Charles R Greathouse IV_, Jul 15 2013
%H Amiram Eldar, <a href="/A207574/b207574.txt">Table of n, a(n) for n = 1..10000</a>
%t Select[Range[1000],Divisible[#+2,EulerPhi[#]+2]&]
%o (PARI) isA207574(n)={
%o if( (n+2) % (eulerphi(n)+2) ==0,1,0) ;
%o }
%o {
%o for(n=1,200,
%o if (isA207574(n) , print(n)) ;
%o ) ;
%o } /* _R. J. Mathar_, Feb 23 2012 */
%Y Cf. A000010, A207575, A202855, A203966.
%K nonn,easy
%O 1,2
%A _José María Grau Ribas_, Feb 19 2012
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