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A071846 phi(n) + phi(reverse(n)) = sigma(n). 0
3, 26, 221, 635, 1702, 4945, 5038, 26596, 27927, 62783, 195723, 210221, 364287, 489955, 495995, 525833, 901303, 909503, 2747761, 2747761, 2941119, 3926146, 4463651, 4484831, 4630475, 4769947, 5531305, 6099313, 6482845, 6917881 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..30.

EXAMPLE

phi(221) + phi(reverse(221)) = phi(221) + phi(122) = 192 + 60 = 252 = sigma(221).

MATHEMATICA

r = {}; Do[ If[ EulerPhi[n] + EulerPhi[ FromDigits[ Reverse[ IntegerDigits[n]]]] == DivisorSigma[1, n], r = Append[r, n]], {n, 1, 10^7}]; r

CROSSREFS

Sequence in context: A037790 A037671 A037797 * A067858 A052141 A062793

Adjacent sequences:  A071843 A071844 A071845 * A071847 A071848 A071849

KEYWORD

base,nonn

AUTHOR

Joseph L. Pe, Jun 09 2002

EXTENSIONS

Edited and extended by Robert G. Wilson v, Jun 11 2002

STATUS

approved

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Last modified October 14 11:43 EDT 2019. Contains 327996 sequences. (Running on oeis4.)