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Search: id:A103113
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| A103113 |
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Numbers n such that phi(n)=phi(d_1^d_1)*phi(d_2^d_2)*...*phi(d_k^d_k) where d_1 d_2 ... d_k is the decimal expansion of n. |
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+0
2
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| 1, 113125, 2322432, 21332611, 2115124224, 3111423252, 3412115322, 12451223232
(list; graph; listen)
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OFFSET
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1,2
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COMMENT
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Next term is greater than 10^11.
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EXAMPLE
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21332611 is in the sequence because phi(21332611)=phi(2^2)*phi(1^1)*
phi(3^3)*phi(3^3)*phi(2^2)*phi(6^6)*phi(1^1)*phi(1^1).
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MATHEMATICA
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Do[h=IntegerDigits[m]; l=Length[h]; If[Min[h]>0&&EulerPhi[m]== Product[EulerPhi[h[[k]]^h[[k]]], {k, l}], Print[m]], {m, 200000000}]
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CROSSREFS
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Cf. A104898.
Sequence in context: A111332 A151841 A102497 this_sequence A122511 A066790 A135411
Adjacent sequences: A103110 A103111 A103112 this_sequence A103114 A103115 A103116
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KEYWORD
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more,nonn,base
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AUTHOR
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Farideh Firoozbakht (mymontain(AT)yahoo.com), Mar 29 2005
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EXTENSIONS
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Four more terms from Max Alekseyev (maxale(AT)gmail.com), May 10 2009
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