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%I #13 Jun 25 2018 03:22:29
%S 35,99,357,495,1672,2108,3135,3465,3692,5152,11704,14756,15800,18375,
%T 20026,23374,23560,25714,25844,33915,35074,39585,49196,55154,56134,
%U 66040,86900,99484,104140,105105,110600,116116,124558,141340,157586
%N Numbers k such that usigma(k) = phi(k)*omega(k), where omega(k) is the number of distinct prime divisors of k.
%H Harry J. Smith, <a href="/A063795/b063795.txt">Table of n, a(n) for n = 1..200</a>
%o (PARI) us(n) = sumdiv(n,d, if(gcd(d,n/d)==1,d));
%o for(n=1,10^7, if(us(n)==eulerphi(n)*omega(n),print(n)))
%o (PARI) us(n) = sumdiv(n, d, if(gcd(d, n/d)==1, d))
%o { n=0; for (m=1, 10^9, if(us(m)==eulerphi(m)*omega(m), write("b063795.txt", n++, " ", m); if (n==200, break)) ) } \\ _Harry J. Smith_, Aug 31 2009
%Y Cf. A034448.
%K nonn
%O 1,1
%A _Jason Earls_, Aug 18 2001
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