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A074786
Numbers k such that phi(k) = Sum_{d|k} 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
OFFSET
1,2
LINKS
PROG
(PARI) isok(n) = eulerphi(n) == sumdiv(n, d, core(d)); \\ Michel Marcus, Aug 09 2013
CROSSREFS
Sequence in context: A093299 A196645 A196600 * A249335 A338258 A201044
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Sep 07 2002
EXTENSIONS
More terms from Michel Marcus, Aug 09 2013
STATUS
approved