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A117690
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Cubes for which both the sum of the digits and the product of the digits are squares.
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0
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0, 1, 1000, 27000, 216000, 970299, 1000000, 1860867, 2146689, 4019679, 5000211, 10077696, 14348907, 21717639, 26198073, 27000000, 27818127, 29503629, 36926037, 37933056, 57960603, 62099136, 67917312, 80621568, 84027672
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,3
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EXAMPLE
| 2146689 is in the sequence because it is a cube and (1)the sum of its digits 2+1+4+6+6+8+9=36 is a square and (2)the product of its digits 2*1*4*6*6*8*9=20736 is also a square.
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MATHEMATICA
| okQ[n_]:=Module[{idn=IntegerDigits[n]}, IntegerQ[Sqrt[Total[idn]]] && IntegerQ[Sqrt[Times@@idn]]]; Select[Range[0, 450]^3, okQ] (* From Harvey P. Dale, Aug 24 2011 *)
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CROSSREFS
| Cf. A000290, A000578.
Sequence in context: A017643 A161770 A004632 * A186936 A185747 A029799
Adjacent sequences: A117687 A117688 A117689 * A117691 A117692 A117693
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KEYWORD
| nonn,base
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AUTHOR
| Luc Stevens (lms022(AT)yahoo.com), Apr 12 2006
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EXTENSIONS
| Corrected (by inserting a(15)=26198073) by Harvey P. Dale, Aug 24 2011
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