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%I #25 Jun 25 2018 03:58:49
%S 33,72,1293,4187,7169,8466,23086,24881,25019,59987,77057,143369,
%T 150419,176715,205727,215069,220817,359499,418307,1239869,1887239,
%U 2123583,2229011,2262107,2303837,2458397,2502977,3495954,3693419,4279859
%N Solutions to phi(x + omega(x)) = phi(x) + d(x), where phi() = A000010(), d() = A000005() and omega() = A001221().
%H Giovanni Resta, <a href="/A063868/b063868.txt">Table of n, a(n) for n = 1..735</a> (terms < 10^11, first 60 terms from Harry J. Smith)
%t Select[Range[5000], EulerPhi[# + PrimeNu[#]] == EulerPhi[#] + DivisorSigma[0, #] &] (* _G. C. Greubel_, Apr 23 2017 *)
%o (PARI) for(n=1,10^7, if(eulerphi(n+omega(n))==eulerphi(n)+numdiv(n),print1(n,",")))
%o (PARI) { n=0; for (m=1, 10^9, if(eulerphi(m + omega(m)) == eulerphi(m) + numdiv(m), write("b063868.txt", n++, " ", m); if (n==60, break)) ) } \\ _Harry J. Smith_, Sep 01 2009
%Y Cf. A000010, A000005, A001221.
%K nonn
%O 1,1
%A _Jason Earls_, Aug 26 2001
%E a(20) from _Thomas Baruchel_, Oct 19 2003
%E a(21)-a(30) from _Donovan Johnson_, Aug 03 2009
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