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A230028
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Numbers n such that phi(n) = reversal(n-20).
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1
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OFFSET
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1,1
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COMMENTS
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If p=10^m+3 is prime then 8*p is in the sequence.
84803024 is the only known term of the sequence which is not of this form.
a(7) > 10^11. - Giovanni Resta, Dec 13 2013
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LINKS
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Table of n, a(n) for n=1..6.
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EXAMPLE
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phi(104)=48=reversal(84)=reversal(104-20).
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MATHEMATICA
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Do[If[EulerPhi[n]==FromDigits[Reverse[IntegerDigits[n-20]]], Print[n]], {n, 21, 90000000}]
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CROSSREFS
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Cf. A000010, A004086.
Sequence in context: A206014 A106298 A337145 * A340898 A132434 A187589
Adjacent sequences: A230025 A230026 A230027 * A230029 A230030 A230031
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KEYWORD
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nonn,base,bref,more
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AUTHOR
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Farideh Firoozbakht, Dec 13 2013
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EXTENSIONS
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a(6) from Giovanni Resta, Dec 13 2013
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STATUS
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approved
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