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A069225
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Numbers n such that phi(n) is the reversal of sigma(n).
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3
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1, 65, 2771, 10920, 158804, 2413091, 16636354, 117650080, 140766297, 630947067, 4639526938
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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EXAMPLE
| phi(65) = 48 = reversal(84) = reversal(sigma(65)), so 65 belongs to the sequence.
n=2413091, sigma[n]=2528032, phi[n]=2308152=rev[sigma[n]].
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MATHEMATICA
| Select[Range[10^6], EulerPhi[ # ] == FromDigits[Reverse[IntegerDigits[DivisorSigma[1, # ]]]] &]
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CROSSREFS
| Sequence in context: A004354 A016111 A075474 * A133853 A188693 A206876
Adjacent sequences: A069222 A069223 A069224 * A069226 A069227 A069228
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KEYWORD
| base,nonn
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AUTHOR
| Joseph L. Pe (joseph_l_pe(AT)hotmail.com), Apr 12 2002
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EXTENSIONS
| a(6)-a(8) from Labos E. (labos(AT)ana.sote.hu), Oct 22 2004
a(9)-a(11) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Jan 14 2011
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