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A153427
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Numbers n such that phi(n)=p^2, where p is product of digits of n.
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1
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1, 12, 125, 451, 4612, 5412, 8313, 22165, 31815, 34125, 43216, 62232, 111398, 115264, 115625, 126225, 142352, 191425, 194313, 235431, 243135, 261532, 265421, 632613, 726313, 852125, 962312, 1142536, 1148316, 1156324, 1162825, 1183491
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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EXAMPLE
| phi(2228224)=(2*2*2*8*2*2*4)^2, so 2228224 is in the sequence.
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MATHEMATICA
| Do[If[Apply[Times, IntegerDigits[n]]^2==EulerPhi[n], Print[n]], {n, 1200000}]
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CROSSREFS
| Cf. A153426, A153428.
Sequence in context: A045507 A155595 A070312 * A178626 A061114 A015792
Adjacent sequences: A153424 A153425 A153426 * A153428 A153429 A153430
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KEYWORD
| base,easy,nonn
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AUTHOR
| Farideh Firoozbakht (mymontain(AT)yahoo.com), Jan 02 2009
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