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A107654
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Numbers n such that if sum of the proper divisors of n is equal to m then n = phi(m).
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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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Next term is greater than 65*10^6.
241287413760 and 6094936793088000 are also terms - Donovan Johnson, Aug 08 2012
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LINKS
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EXAMPLE
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62000640 is in the sequence because sigma(62000640)-62000640 = 187545888 and phi(187545888) = 62000640.
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MATHEMATICA
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Do[If[n == EulerPhi[DivisorSigma[1, n]-n], Print[n]], {n, 65000000}]
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CROSSREFS
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KEYWORD
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more,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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