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A196200
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Numbers k such that Euler phi(Dedekind psi(k)) > k.
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1
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39270, 53130, 71610, 78540, 82110, 106260, 108570, 117810, 122430, 143220, 157080, 159390, 164010, 164220, 212520, 214830, 217140, 235620, 244860, 246330, 247170, 286440, 293370, 314160, 318780, 325710, 328020, 328440, 353430, 367290, 425040, 429660, 434280
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OFFSET
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1,1
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COMMENTS
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Counterexamples to a conjecture by Sandor.
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LINKS
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MATHEMATICA
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Select[Range[39270, 434280], EulerPhi[# * Sum[MoebiusMu[d]^2 / d, {d, Divisors[#]}]] > # &] (* Indranil Ghosh, Mar 11 2017 *)
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PROG
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(PARI) a(m) = {for (n=1, m, if (eulerphi(n * sumdiv( n, d, moebius(d)^2 / d)) > n, print1(n, ", ")); ); }
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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