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A018889 Shortest representation as sum of positive cubes requires exactly 8 cubes. 9
15, 22, 50, 114, 167, 175, 186, 212, 231, 238, 303, 364, 420, 428, 454 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Wieferich proved that 167 is the unique prime in this sequence. - Jonathan Vos Post, Sep 23 2006

REFERENCES

J. Bohman and C.-E. Froberg, Numerical investigation of Waring's problem for cubes, Nordisk Tidskr. Informationsbehandling (BIT) 21 (1981), 118-122.

K. S. McCurley, An effective seven-cube theorem, J. Number Theory, 19 (1984), 176-183.

Joe Roberts, Lure of the Integers, entry 239.

LINKS

Table of n, a(n) for n=1..15.

G. L. Honaker, Jr. and Chris Caldwell, et al., A Prime Curios Page.

Eric Weisstein's World of Mathematics, Cubic Number

Eric Weisstein's World of Mathematics, Warings Problem

Index entries for sequences related to sums of cubes

MATHEMATICA

max = 500; nn = Union[(#*#).# & /@ Tuples[Range[0, 7], {7}]][[1 ;; max]]; Select[{#, PowersRepresentations[#, 8, 3]} & /@ Complement[Range[max], nn] , #[[2]] != {} &][[All, 1]] (* Jean-Fran├žois Alcover, Jul 21 2011 *)

CROSSREFS

Subsequence of A018888.

Sequence in context: A006615 A114867 A109288 * A186525 A236107 A065728

Adjacent sequences:  A018886 A018887 A018888 * A018890 A018891 A018892

KEYWORD

nonn,fini,full,nice

AUTHOR

Anon

EXTENSIONS

Corrected by Arlin Anderson (starship1(AT)gmail.com). Additional comments from Jud McCranie.

STATUS

approved

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Last modified January 21 21:01 EST 2017. Contains 281110 sequences.