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%I
%S 1,3,4,12,14,24,28,36,48,60,72,78,84,96,120,144,168,180,192,240,248,
%T 264,288,312,336,360,420,432,480,496,576,620,672,684,720,780,792,798,
%U 840,864,924,936,960,1008,1056,1080,1092,1104,1176,1240,1260,1344,1368
%N Numbers n such that the equation lcm(sigma(x),phi(x))=n has solutions.
%o (PARI) for(n=1,2000,if(0<sum(i=1,n,if(lcm(sigma(i),eulerphi(i))-n,0,1)),print1(n,",")))
%K easy,nonn
%O 1,2
%A _Benoit Cloitre_, May 10 2002
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