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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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7
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1, 65, 2771, 10920, 158804, 2413091, 16636354, 117650080, 140766297, 630947067, 4639526938, 153896850898
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OFFSET
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1,2
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COMMENTS
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LINKS
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EXAMPLE
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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
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Select[Range[10^6], EulerPhi[ # ] == FromDigits[Reverse[IntegerDigits[DivisorSigma[1, # ]]]] &]
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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