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A063868
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Solutions to phi(x + omega(x)) = phi(x) + d(x), where phi() = A000010(), d() = A000005() and omega() = A001221().
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1
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33, 72, 1293, 4187, 7169, 8466, 23086, 24881, 25019, 59987, 77057, 143369, 150419, 176715, 205727, 215069, 220817, 359499, 418307, 1239869, 1887239, 2123583, 2229011, 2262107, 2303837, 2458397, 2502977, 3495954, 3693419, 4279859
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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Select[Range[5000], EulerPhi[# + PrimeNu[#]] == EulerPhi[#] + DivisorSigma[0, #] &] (* G. C. Greubel, Apr 23 2017 *)
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PROG
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(PARI) for(n=1, 10^7, if(eulerphi(n+omega(n))==eulerphi(n)+numdiv(n), print1(n, ", ")))
(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
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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