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A112721
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Numbers n such that phi(n)=d_1^1+d_2^2+...+d_k^k where d_1 d_2 ... d_k is the decimal expansion of n.
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1
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1, 44, 84, 5676, 32186, 35097, 128476, 527048, 700298, 12141094, 43874279, 58730238, 303387848, 2277279428
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| a(15) > 6*10^10. [From Donovan Johnson (donovan.johnson(AT)yahoo.com), Nov 09 2010]
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EXAMPLE
| phi(12141094)=1^1+2^2+1^3+4^4+1^5+0^6+9^7+4^8 so 12141094 is in
the sequence.
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MATHEMATICA
| Do[d=IntegerDigits[n]; k=Length[d]; If[EulerPhi[n]==Sum[d[[j]]^j, {j, k}], Print[n]], {n, 30000000}]
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CROSSREFS
| Cf. A032799, A035138, A112718-20.
Sequence in context: A043209 A043989 A050272 * A195816 A118087 A044182
Adjacent sequences: A112718 A112719 A112720 * A112722 A112723 A112724
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KEYWORD
| base,fini,more,nonn
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AUTHOR
| Farideh Firoozbakht (mymontain(AT)yahoo.com), Sep 17 2005
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EXTENSIONS
| a(11)-a(12) from Farideh Firoozbakht (mymontain(AT)yahoo.com), Jan 04 2009
a(13)-a(14) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Nov 09 2010
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