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A153428
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Numbers n such that phi(n)=p^3, where p is product of digits of n.
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1
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1, 14611, 141152, 2831112, 113216152, 419521121, 5342121213, 7112216125, 11191442171, 11371542112, 12192256111, 12327134121, 12432712113, 13161313512, 14132133215, 113335111416, 127131142512, 133412214117
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| There is no further term up to 3*10^8.
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EXAMPLE
| phi(113216152)=(1*1*3*2*1*6*1*5*2)^3, so 113216152 is in the sequence.
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MATHEMATICA
| Do[If[Apply[Times, IntegerDigits[n]]^3==EulerPhi[n], Print[n]], {n, 300000000}]
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CROSSREFS
| Cf. A153426, A153427.
Sequence in context: A202489 A175972 A175973 * A032736 A032738 A133858
Adjacent sequences: A153425 A153426 A153427 * A153429 A153430 A153431
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KEYWORD
| base,nonn
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AUTHOR
| Farideh Firoozbakht (mymontain(AT)yahoo.com), Jan 02 2009
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EXTENSIONS
| a(6)-a(18) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Nov 01 2010
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