

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
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OFFSET

1,1


COMMENTS

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


REFERENCES

Joe Roberts, Lure of the Integers, entry 239.


LINKS

Table of n, a(n) for n=1..15.
Jan Bohman and CarlErik Froberg, Numerical investigation of Waring's problem for cubes, Nordisk Tidskr. Informationsbehandling (BIT) 21 (1981), 118122.
G. L. Honaker, Jr. and Chris Caldwell, et al., A Prime Curios Page.
K. S. McCurley, An effective sevencube theorem, J. Number Theory, 19 (1984), 176183.
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]] (* JeanFrançois 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



