Some results for a "Waring-like Problem". ANY rational N is, in an
infinite number of _non-trivial_ ways:
1) the sum of 3 rational 3rd powers. (Ryley's Theorem)
2) the sum of 6 rational 5th powers. (Choudhry)
3) the sum of 8 rational 7th powers. (Choudhry)
All results are dependent on certain algebraic identities, but whether
(2) and (3) can be reduced to 5 and 7 sums, respectively, is unknown.
See here: http://sites.google.com/site/tpiezas/001
- Titus