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A074786 Numbers n such that phi(n) = sum(d|n,core(d)) where core(x) is the squarefree part of x (A007913). 1
1, 99, 1080, 1836, 4743, 5670, 7644, 8307, 14384, 14784, 15225, 15824, 16065, 20300, 21584, 25704, 29760, 34544, 46816, 71568, 94240, 128412, 169290, 264160, 266266, 312480, 331731, 364941, 404550, 445050, 454575, 458052, 479655, 497781 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Donovan Johnson, Table of n, a(n) for n = 1..500

PROG

(PARI) isok(n) = eulerphi(n) == sumdiv(n, d, core(d)); \\ Michel Marcus, Aug 09 2013

CROSSREFS

Sequence in context: A093299 A196645 A196600 * A249335 A201044 A196577

Adjacent sequences:  A074783 A074784 A074785 * A074787 A074788 A074789

KEYWORD

nonn

AUTHOR

Benoit Cloitre, Sep 07 2002

EXTENSIONS

More terms from Michel Marcus, Aug 09 2013

STATUS

approved

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Last modified February 20 22:51 EST 2019. Contains 320362 sequences. (Running on oeis4.)