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A067238 Numbers n such that sigma(n) = bigomega(n) * phi(n). 1
35, 248, 357, 1672, 3135, 3596, 3956, 5396, 8636, 20026, 23374, 24244, 25714, 25758, 29512, 33915, 35074, 39585, 51688, 55154, 56134, 61344, 107156, 142240, 157586, 208280, 282680, 316274, 373065, 383656, 389732, 427924, 435435, 470764 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Charles R Greathouse IV and Donovan Johnson, Table of n, a(n) for n = 1..1000 (first 500 terms from Charles R Greathouse IV)

MAPLE

with(numtheory); A067238:=n->`if`(sigma(n)=bigomega(n)*phi(n), n, NULL); seq(A067238(n), n=1..10^6); # Wesley Ivan Hurt, Nov 21 2013

PROG

(PARI) isok(n) = sigma(n) == bigomega(n)*eulerphi(n); \\ Michel Marcus, Nov 21 2013

(PARI) is(n)=n=factor(n); sigma(n)==bigomega(n)*eulerphi(n) \\ Charles R Greathouse IV, Nov 21 2013

CROSSREFS

Sequence in context: A068722 A255584 A113941 * A267022 A145014 A090646

Adjacent sequences:  A067235 A067236 A067237 * A067239 A067240 A067241

KEYWORD

nonn

AUTHOR

Benoit Cloitre, Feb 20 2002

STATUS

approved

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Last modified April 5 13:34 EDT 2020. Contains 333241 sequences. (Running on oeis4.)