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 A196200 Numbers such that Euler Phi(Dedekind Psi(n)) > n. 1
 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Counterexamples to a conjecture by Sandor. LINKS Indranil Ghosh, Table of n, a(n) for n = 1..66 (terms < 1000000) Jozsef Sandor, On the Composition of Some Arithmetic Functions, II, Journal of Inequalities in Pure and Applied Mathematics (JIPAM), Volume 6, Issue 3, Article 73, 2005 MATHEMATICA Select[Range[39270, 434280], EulerPhi[# * Sum[MoebiusMu[d]^2 / d, {d, Divisors[#]}]] > # &] (* Indranil Ghosh, Mar 11 2017 *) PROG (PARI) a(m) = {for (n=1, m, if (eulerphi(n * sumdiv( n, d, moebius(d)^2 / d)) > n, print1(n, ", ")); ); } CROSSREFS Cf. A000010, A001615. Sequence in context: A233955 A250515 A031667 * A274128 A144306 A234033 Adjacent sequences:  A196197 A196198 A196199 * A196201 A196202 A196203 KEYWORD nonn AUTHOR Michel Marcus, Dec 21 2012 STATUS approved

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Last modified April 22 10:24 EDT 2019. Contains 322330 sequences. (Running on oeis4.)