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%I #16 May 28 2013 13:30:21
%S 1,6,36,64,105,114,135,1980,2016,3072,5120,7056,7840,9216,16320,18720,
%T 18900,23100,23622,24003,25536,26088,26733,28455,29078,29337,29700,
%U 29760,30597,30894,30912,31155,31496,31758,32361,33782,34020,34286,36000,36036,36099
%N Numbers such that sigma(phi(tau(n)))=tau(phi(sigma(n))).
%H Paolo P. Lava and T. D. Noe, <a href="/A226119/b226119.txt">Table of n, a(n) for n = 1..1000</a> (first 270 terms from Paolo P. Lava)
%e 29337 is in the sequence since:
%e sigma(29337)=49152 -> phi(49152)=16384 -> tau(16384)=15.
%e tau(29337)=16 -> phi(16)=8 -> sigma(8)=15.
%p with(numtheory); A226119:=proc(q) local n;
%p for n from 1 to q do
%p if sigma(phi(tau(n)))=tau(phi(sigma(n))) then print(n);
%p fi; od; end: A226119(10^6);
%t Select[Range[36099], DivisorSigma[1, EulerPhi[DivisorSigma[0, #]]] == DivisorSigma[0, EulerPhi[DivisorSigma[1, #]]] &] (* _T. D. Noe_, May 28 2013 *)
%Y Cf. A000005, A000010, A000203, A033632, A067160, A076361, A226117, A226118.
%K nonn
%O 1,2
%A _Paolo P. Lava_, May 27 2013
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