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 A058652 Squarefree n such that sigma(phi(n)) = phi(sigma(n)). 1
 1, 29262, 114630, 160986, 179562, 252978, 502878, 528954, 780258, 908070, 1080906, 1826454, 2460786, 2870142, 3934686, 5086722, 5493030, 6001206, 6183078, 6621270, 6668634, 8808234, 9298110, 9752190, 10479282, 11707518, 12263334, 12928254, 13513278 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Donovan Johnson, Table of n, a(n) for n = 1..500 MATHEMATICA Select[ Range[ 10^7 ], DivisorSigma[ 1, EulerPhi[ # ] ] == EulerPhi[ DivisorSigma[ 1, # ] ] && Union[ Transpose[ FactorInteger[ # ] ] [ [ 2 ] ] ] == {1} & ] CROSSREFS Cf. A033632. Sequence in context: A252860 A206470 A194619 * A250940 A186566 A083740 Adjacent sequences: A058649 A058650 A058651 * A058653 A058654 A058655 KEYWORD nonn AUTHOR Robert G. Wilson v, Dec 26 2000 EXTENSIONS Prepended missing a(1)=1, Donovan Johnson, Mar 03 2012. STATUS approved

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Last modified December 9 01:07 EST 2023. Contains 367681 sequences. (Running on oeis4.)