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A228174 Numbers representable as x^x * y^y, with x > y > 1. 0
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A subsequence of A156223.

LINKS

Table of n, a(n) for n=1..25.

EXAMPLE

a(7) = 4^4 * 5^5 = 800000.

MATHEMATICA

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 *)

CROSSREFS

Cf. A000312, A156223.

Sequence in context: A202194 A203373 A292343 * A184201 A101213 A202608

Adjacent sequences:  A228171 A228172 A228173 * A228175 A228176 A228177

KEYWORD

nonn

AUTHOR

Alex Ratushnyak, Nov 02 2013

STATUS

approved

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Last modified December 15 04:23 EST 2019. Contains 329991 sequences. (Running on oeis4.)