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A196520
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Smallest Friedman number of order n.
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0
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OFFSET
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1,1
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COMMENTS
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More terms from a=9 to a=12 are 22528399544939174411840147874772641, 147808829414345923316083210206383297601, 1427247692705959881058285969449495136382746624 and 91343852333181432387730302044767688728495783936.
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LINKS
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FORMULA
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All numbers of this kind are perfect powers.
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EXAMPLE
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Since 25 is the smallest Friedman number, it is the smallest Friedman number of order 1.
279936 = 6^7 = (9 - 3)^(9 - 2), together using the digits of the number itself. Hence it is the smallest Friedman number of order 2.
31381059609 = 9^11 = 9^(5+6) = 3^(30-8+0), together using the digits of the number itself. Hence it is the smallest Friedman number of order 3.
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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