On $x^n + y^n = \lowercase{n!} z^n$
Communications in Mathematics, Tome 26 (2018) no. 1, pp. 11-14
Cet article a éte moissonné depuis la source Czech Digital Mathematics Library
In p.~219 of R.K. Guy's \emph {Unsolved Problems in Number Theory}, 3rd edn., Springer, New York, 2004, we are asked to prove that the Diophantine equation $x^{n} + y^{n} = \lowercase {n!} z^{n}$ has no integer solutions with $n\in \mathbb {N_{+}}$ and $n>2$. But, contrary to this expectation, we show that for $n = 3$, this equation has infinitely many primitive integer solutions, i.e.~the solutions satisfying the condition $\gcd (x, y, z)=1$.
In p.~219 of R.K. Guy's \emph {Unsolved Problems in Number Theory}, 3rd edn., Springer, New York, 2004, we are asked to prove that the Diophantine equation $x^{n} + y^{n} = \lowercase {n!} z^{n}$ has no integer solutions with $n\in \mathbb {N_{+}}$ and $n>2$. But, contrary to this expectation, we show that for $n = 3$, this equation has infinitely many primitive integer solutions, i.e.~the solutions satisfying the condition $\gcd (x, y, z)=1$.
Classification :
11D41, 11D72
Keywords: Diophantine equation $x^{n} + y^{n} = \lowercase {n!} z^{n}$; Diophantine equation $x^{3} + y^{3} = \lowercase {3!} z^{3}$; unsolved problems; number theory.
Keywords: Diophantine equation $x^{n} + y^{n} = \lowercase {n!} z^{n}$; Diophantine equation $x^{3} + y^{3} = \lowercase {3!} z^{3}$; unsolved problems; number theory.
@article{COMIM_2018_26_1_a1,
author = {Jena, Susil Kumar},
title = {On $x^n + y^n = \lowercase{n!} z^n$},
journal = {Communications in Mathematics},
pages = {11--14},
year = {2018},
volume = {26},
number = {1},
mrnumber = {3827140},
zbl = {06996470},
language = {en},
url = {http://geodesic.mathdoc.fr/item/COMIM_2018_26_1_a1/}
}
Jena, Susil Kumar. On $x^n + y^n = \lowercase{n!} z^n$. Communications in Mathematics, Tome 26 (2018) no. 1, pp. 11-14. http://geodesic.mathdoc.fr/item/COMIM_2018_26_1_a1/
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