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A071525
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Numbers n such that sigma(phi(n)) = reversal(n).
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2
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OFFSET
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1,2
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COMMENTS
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There are no other terms up to 10^7. - Jason Earls, Jun 04 2002
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LINKS
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EXAMPLE
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sigma(phi(304)) = 403 = reverse(304).
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MATHEMATICA
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Select[Range[10^5], DivisorSigma[1, EulerPhi[ # ]] == FromDigits[Reverse[IntegerDigits[ # ]]] &]
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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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