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A117689
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Cubes for which the product of the digits is a square.
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1
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0, 1, 343, 1000, 1331, 4096, 8000, 10648, 19683, 27000, 39304, 50653, 64000, 74088, 79507, 103823, 110592, 125000, 140608, 148877, 205379, 216000, 238328, 250047, 300763, 328509, 343000, 389017, 405224, 493039, 512000, 551368, 592704, 636056
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OFFSET
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0,3
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COMMENTS
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Any cube with a zero digit is a term of this sequence. Of the first 10,000 terms, only 331 have no zero digits. The largest such zero-free cube in the first 10,000 terms is 2956841564977. - Harvey P. Dale, Aug 22 2021
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LINKS
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Harvey P. Dale, Table of n, a(n) for n = 0..10000
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EXAMPLE
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19683 is in the sequence because it is a cube and the product of its digits 1*9*6*8*3=1296 is a square.
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MATHEMATICA
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Select[Range[0, 100]^3, IntegerQ[Sqrt[Times@@IntegerDigits[#]]]&] (* Harvey P. Dale, Aug 22 2021 *)
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CROSSREFS
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Cf. A000290, A000578.
Sequence in context: A336354 A269346 A202852 * A178374 A179147 A047739
Adjacent sequences: A117686 A117687 A117688 * A117690 A117691 A117692
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KEYWORD
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nonn,base
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AUTHOR
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Luc Stevens (lms022(AT)yahoo.com), Apr 12 2006
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STATUS
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approved
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