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8, 125, 512, 1331, 2744, 4913, 8000, 12167, 17576, 24389, 32768, 42875, 54872, 68921, 85184, 103823, 125000, 148877, 175616, 205379, 238328, 274625, 314432, 357911, 405224, 456533, 512000, 571787, 636056, 704969, 778688, 857375, 941192
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,1
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COMMENTS
| Also the perfect cubes with digital root 8. [Proof: perfect cubes are either of the form (3n)^3 or of the form (3n+1)^3 or of the form (3n+2)^3. These subsets have digital root 0, 1 and 8 respectively.] [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Oct 02 2008]
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REFERENCES
| Amarnath Murthy, Fabricating a perfect cube with a given valid digit sum (to be published)
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LINKS
| Harry J. Smith, Table of n, a(n) for n=0,...,1000
M. L. Perez et al., eds., Smarandache Notions Journal
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FORMULA
| a(n) = (3n-1)^3 = A016789(n-1)^3. - Nathaniel Johnston, May 04 2011
G.f.: (8+93*x+60*x^2+x^3)/(1-4*x+6*x^2-4*x^3+x^4). [Colin Barker, Jan 02 2012]
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EXAMPLE
| 2744=(3*4+2)^3.
17576=(3*8+2)^3.
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PROG
| (PARI) { for (n=0, 1000, write("b016791.txt", n, " ", (3*n + 2)^3) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Jul 18 2009]
(PARI) { b=0; for (n=1, 1000, until (s==8, b++; s=b^3; s-=9*(s\9)); write("b016791.txt", n, " ", b^3) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Jul 18 2009]
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CROSSREFS
| Cf. A054966, A016779, A073636.
Sequence in context: A065082 A053058 A050803 * A061103 A110272 A033536
Adjacent sequences: A016788 A016789 A016790 * A016792 A016793 A016794
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KEYWORD
| nonn,easy
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
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EXTENSIONS
| More terms from Harry J. Smith (hjsmithh(AT)sbcglobal.net), Jul 18 2009
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