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Numbers k such that j mod phi(j) < k mod phi(k) for any j < k.
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%I #10 Feb 11 2021 01:27:59

%S 1,3,9,15,21,33,39,45,63,75,99,117,135,189,225,231,255,273,285,345,

%T 375,399,405,435,465,555,609,615,645,675,693,705,765,819,855,915,1005,

%U 1035,1095,1125,1185,1215,1245,1275,1395,1425,1515,1545,1605,1617,1665,1725

%N Numbers k such that j mod phi(j) < k mod phi(k) for any j < k.

%o (PARI) for(n=1,2000,if(sum(i=1,n-1,sign(n%eulerphi(n)-i%eulerphi(i)))==n-1,print1(n,",")))

%K easy,nonn

%O 1,2

%A _Benoit Cloitre_, Jun 02 2002