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A112419
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Prime Friedman numbers.
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0
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127, 347, 2503, 12101, 12107, 12109, 15629, 15641, 15661, 15667, 15679, 16381, 16447, 16759, 16879, 19739, 21943, 27653, 28547, 28559, 29527, 29531, 32771, 32783, 35933, 36457, 39313, 39343, 43691, 45361, 46619, 46633, 46643, 46649
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| A Friedman number is one which is expressible in a nontrivial manner with the same digits by means of the arithmetic operations +, -, *, "divided by" along with ^ and digit concatenation.
Ron Kaminsky notes that, by Dirichlet's theorem, this sequence is infinite; see Friedman link.
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LINKS
| Erich Friedman, Problem of the Month (August 2000).
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EXAMPLE
| Since the following primes have expressions 16381 = (1+1)^(6+8) - 3 ; 16447 = -1+64+4^7 ; 16759 = 7^5 - 6*(9-1), they are in the sequence.
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CROSSREFS
| Cf. A036057.
Sequence in context: A031933 A080035 A162004 * A142201 A142889 A095312
Adjacent sequences: A112416 A112417 A112418 * A112420 A112421 A112422
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KEYWORD
| nonn,base
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AUTHOR
| Lekraj Beedassy (blekraj(AT)yahoo.com), Jan 23 2007
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EXTENSIONS
| Corrected and extended by Ray Chandler (rayjchandler(AT)sbcglobal.net), Apr 24 2010
Comment from Charles R Greathouse IV (charles.greathouse(AT)case.edu), Apr 30 2010
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