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A228174
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Numbers representable as x^x * y^y, with x > y > 1.
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0
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108, 1024, 6912, 12500, 84375, 186624, 800000, 1259712, 3294172, 11943936, 22235661, 67108864, 145800000, 210827008, 452984832, 1549681956, 2573571875, 4294967296, 10460353203, 38423222208, 40000000000, 52428800000, 99179645184, 270000000000, 782757789696
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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a(7) = 4^4 * 5^5 = 800000.
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MATHEMATICA
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nn = 12; Select[Rest[Union[Flatten[Table[If[x > y, x^x*y^y, 0], {x, 3, nn}, {y, 2, nn - 1}]]]], # <= 4*nn^nn &] (* T. D. Noe, Nov 04 2013 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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