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%I
%S 1,3,5,7,9,11,13,17,19,21,23,25,27,29,31,33,35,37,39,41,43,47,49,51,
%T 53,55,57,59,61,65,67,69,71,73,77,79,81,83,85,87,89,91,93,95,97,99,
%U 101,103,107,109,111,113,115,117,119,121,123,125,127,129,131,133,137
%N Numbers n such that n, sigma(n) and phi(n) form an integer triangle, where sigma=A000203 is the divisor sum and phi=A000010 the totient.
%C a(n)<=A000203(a(n))+A000010(a(n)), A000203(a(n))<=a(n)+A000010(a(n)), A000010(a(n))<=a(n)+A000203(a(n)); values are odd, see A084821 for odd numbers which are not in the sequence.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/DivisorFunction.html">Divisor Function</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/TotientFunction.html">Totient Function</a>
%e n=5, a(5)=9: phi(9)=6, sigma(9)=13: (6,9,13)=(A070080(176), A070081(176), A070082(176)).
%o (PARI) is(n)=eulerphi(n)+n>sigma(n) \\ _Charles R Greathouse IV_, Feb 19 2013
%Y Cf. A046022.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Jun 04 2003
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