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%I #22 Nov 09 2014 08:05:53
%S 1,598,1498,54797260
%N Numbers n such that A143615(n) = sigma(n) where sigma(n) = A000203(n).
%C a(5) (if it exists) > 10^8. - _Hiroaki Yamanouchi_, Sep 11 2014
%o (PARI) isok(n) = sum(m=1, n, if (gcd(n,m)==1, numdiv(m))) == sigma(n); \\ _Michel Marcus_, Nov 08 2014
%Y Cf. A000203, A143615.
%K nonn,more
%O 1,2
%A _Naohiro Nomoto_, Aug 05 2012
%E a(4) from _Hiroaki Yamanouchi_, Sep 11 2014
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