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A117690 Cubes for which both the sum of the digits and the product of the digits are squares. 0
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; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..24.

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.

MATHEMATICA

okQ[n_]:=Module[{idn=IntegerDigits[n]}, IntegerQ[Sqrt[Total[idn]]] && IntegerQ[Sqrt[Times@@idn]]]; Select[Range[0, 450]^3, okQ] (* Harvey P. Dale, Aug 24 2011 *)

CROSSREFS

Cf. A000290, A000578.

Sequence in context: A004632 A277397 A250449 * A186936 A185747 A234787

Adjacent sequences:  A117687 A117688 A117689 * A117691 A117692 A117693

KEYWORD

nonn,base

AUTHOR

Luc Stevens (lms022(AT)yahoo.com), Apr 12 2006

EXTENSIONS

Corrected (by inserting a(15)=26198073) by Harvey P. Dale, Aug 24 2011

STATUS

approved

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Last modified December 4 22:42 EST 2021. Contains 349526 sequences. (Running on oeis4.)