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%I #5 Mar 30 2012 17:20:56
%S 9,16,35,45,150,154,234,264
%N phi(a(n)) is equal to the product of (the sum of prime factors and the sum of exponents) of (a(n)).
%C Next term if it exists is greater than 10000000. - C. Ronaldo (aga_new_ac(AT)hotmail.com), Dec 29 2004
%e phi(45)=24, 45=3^2*5^1, (3+5)*(2+1)=24.
%o (PARI) for(n=1,10000000,f=factor(n);l=#f[,1];if(eulerphi(n)==sum(i=1,l,f[i,1])*sum(i=1,l,f[i,2]),print1(n,","))) (Ronaldo)
%Y Cf. A000010, A039697.
%K nonn,more
%O 1,1
%A _Olivier Gérard_
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