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A251363
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Numbers n such that n is the concatenation of distinct prime factors of phi(n), in decreasing order.
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2
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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 1.6*10^8.
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LINKS
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EXAMPLE
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237532 is in the sequence since phi(237532)=23*7*5*3^2*2^4,
832332 is in the sequence since phi(832332)=83*23*3^2*2^4, and
82953292 is in the sequence since phi(82953292)=829*53*29*2^5.
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MATHEMATICA
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a251363[n_Integer] :=
Rest@ Select[Range[n], # == FromDigits[Flatten@ IntegerDigits[
Sort[First@ Transpose@ FactorInteger[EulerPhi[#]], Greater]]] &]; a251363[10^6] (* Michael De Vlieger, Dec 03 2014 *)
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CROSSREFS
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KEYWORD
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nonn,base,more,bref
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AUTHOR
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STATUS
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approved
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