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A117689
Cubes for which the product of the digits is a square.
1
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
OFFSET
0,3
COMMENTS
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
LINKS
EXAMPLE
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.
MATHEMATICA
Select[Range[0, 100]^3, IntegerQ[Sqrt[Times@@IntegerDigits[#]]]&] (* Harvey P. Dale, Aug 22 2021 *)
CROSSREFS
Sequence in context: A336354 A269346 A202852 * A178374 A179147 A047739
KEYWORD
nonn,base
AUTHOR
Luc Stevens (lms022(AT)yahoo.com), Apr 12 2006
STATUS
approved