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A067070
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Cubes for which the product of the digits is a cube > 0.
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1
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1, 8, 24389, 226981, 9393931, 11239424, 17373979, 36264691, 66923416, 94818816, 348913664, 435519512, 463684824, 549353259, 555412248, 743677416, 3929352552, 4982686912, 5526456832, 11329982936, 12374478297, 12681938368, 15142552424
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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REFERENCES
| Felice Russo, A set of new Smarandache Functions, Sequences and conjectures in number theory, American Research Press, Lupton USA.
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LINKS
| Harry J. Smith, Table of n, a(n) for n=1,...,1000
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EXAMPLE
| 24389 is in the sequence because (1) it is a cube, (2) the product of its digits is 2*4*3*8*9=1728 which is a cube >0.
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PROG
| (PARI) ProdD(x)= { local(p=1); while (x>9 && p>0, p*=x%10; x\=10); return(p*x) } iscube(x)= { if (x==0, return(1)); f=factor(x)~; for(i=1, length(f), if (t=f[2, i]%3, return(0))); return(1); } { n=0; for (m=1, 10^10, p=ProdD(m^3); if (p && iscube(p), write("b067070.txt", n++, " ", m^3); if (n==1000, return)) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), May 04 2010]
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CROSSREFS
| Sequence in context: A079172 A173543 A067074 * A115478 A013788 A156178
Adjacent sequences: A067067 A067068 A067069 * A067071 A067072 A067073
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KEYWORD
| nonn,base
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AUTHOR
| Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Jan 05 2002
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EXTENSIONS
| More terms from Sascha Kurz (sascha.kurz(AT)uni-bayreuth.de), Mar 23 2002
One further term from Luc Stevens (lms022(AT)yahoo.com), May 03 2006
Edited by R. J. Mathar, Aug 08 2008
0,2 to 1,2 by Harry J. Smith (hjsmithh(AT)sbcglobal.net), May 04 2010
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