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A058653 Numbers n such that Sigma(Phi(n)) = Phi(Sigma(n)-n). 0
2, 18, 50, 1250, 1980, 6900, 61080, 1369020, 2025660, 2820240, 4003230, 4917360, 8597316, 15396360, 15893010, 28725648, 41427360, 53423760, 148663020, 209752500, 212019024, 222746160, 232210080, 281870316, 298848144, 314121180, 322230180, 385612260, 390760260 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..29.

MATHEMATICA

Select[ Range[ 10^6 ], DivisorSigma[ 1, EulerPhi[ # ] ] == EulerPhi[ DivisorSigma[ 1, # ] - # ] & ]

CROSSREFS

Sequence in context: A048910 A077591 A050808 * A058794 A114109 A085293

Adjacent sequences:  A058650 A058651 A058652 * A058654 A058655 A058656

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Dec 26 2000

EXTENSIONS

a(8)-a(29) from Donovan Johnson, Jan 19 2012

STATUS

approved

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Last modified April 26 09:03 EDT 2019. Contains 322472 sequences. (Running on oeis4.)