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A130913
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Composite solutions to the equation phi(x)+sigma(x)=2*reversal(x).
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OFFSET
| 1,1
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COMMENTS
| For a prime p we have phi(p)+sigma(p)=2*reversal(p) iff p is a palindrome.
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EXAMPLE
| 485700768 is in the sequence because 485700768 is composite and phi(485700768)+sigma(485700768)=1734015168=2*867007584.
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CROSSREFS
| Cf. A130000.
Sequence in context: A206326 A172718 A049360 * A205263 A087534 A183747
Adjacent sequences: A130910 A130911 A130912 * A130914 A130915 A130916
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KEYWORD
| hard,more,nonn,base
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AUTHOR
| Farideh Firoozbakht (mymontain(AT)yahoo.com), Jun 09 2007
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