Infinite Number of Integers which are Sum of 3 Sixth Powers in 2 Ways
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Theorem
There exist an infinite number of positive integers which can be expressed as the sum of $3$ sixth powers in $2$ different ways.
Proof
There are many parametric solutions to $x^6 + y^6 + z^6 = u^6 + v^6 + w^6$. One is given by:
\(\ds x\) | \(=\) | \(\ds 2 m^4 + 4 m^3 n - 5 m^2 n^2 - 12 m n^3 - 9 n^4\) | ||||||||||||
\(\ds y\) | \(=\) | \(\ds 3 m^4 + 9 m^3 n + 18 m^2 n^2 + 21 m n^3 + 9 n^4\) | ||||||||||||
\(\ds z\) | \(=\) | \(\ds -m^4 - 10 m^3 n - 17 m^2 n^2 - 12 m n^3\) | ||||||||||||
\(\ds u\) | \(=\) | \(\ds m^4 - 3 m^3 n - 14 m^2 n^2 - 15 m n^3 - 9 n^4\) | ||||||||||||
\(\ds v\) | \(=\) | \(\ds 3 m^4 + 8 m^3 n + 9 m^2 n^2\) | ||||||||||||
\(\ds w\) | \(=\) | \(\ds 2 m^4 + 12 m^3 n + 19 m^2 n^2 + 18 m n^3 + 9 n^4\) |
This set of solutions also satisfy:
\(\ds x^2 + y^2 + z^2\) | \(=\) | \(\ds u^2 + v^2 + w^2\) | ||||||||||||
\(\ds 3 x + y + z\) | \(=\) | \(\ds 3 u + v + w\) |
![]() | This needs considerable tedious hard slog to complete it. In particular: For people who enjoy degree $24$ polynomials in $2$ unknowns To discuss this page in more detail, feel free to use the talk page. When this work has been completed, you may remove this instance of {{Finish}} from the code.If you would welcome a second opinion as to whether your work is correct, add a call to {{Proofread}} the page. |
Sources
- 1976: Simcha Brudno: Triples of Sixth Powers with Equal Sums (Math. Comp. Vol. 30, no. 135: pp. 646 – 648) www.jstor.org/stable/2005335
- 1986: David Wells: Curious and Interesting Numbers ... (previous) ... (next): $160,426,514$
- 1997: David Wells: Curious and Interesting Numbers (2nd ed.) ... (previous) ... (next): $160,426,514$