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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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1
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1, 113125, 2322432, 21332611, 2115124224, 3111423252, 3412115322, 12451223232, 116222114125, 1141433232511, 2231521231226, 2334121141253, 3222154622111, 4211413132352
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| Next term is greater than 10^13. Conjecture: next term is 15123362231122.
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EXAMPLE
| 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
| 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
| Cf. A104898.
Sequence in context: A102497 A206071 A177275 * A179922 A122511 A172549
Adjacent sequences: A103110 A103111 A103112 * A103114 A103115 A103116
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KEYWORD
| more,nonn,base
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AUTHOR
| Farideh Firoozbakht (mymontain(AT)yahoo.com), Mar 29 2005
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EXTENSIONS
| Four more terms from Max Alekseyev (maxale(AT)gmail.com), May 10 2009
Six more terms from Max Alekseyev (maxale(AT)gmail.com), May 05 2010
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