A graph of Y=X3
- 2017X shows the characteristic cubic form. N will just shift it up or down. What we seek is the value of N that will make all solutions integers.
This is equivalent to finding three values of X in the above equation that give the same value of Y. From the graph, these must be in the interval [-51,51].
What I did was make a take of X,Y and then sorted by Y. A quick scan found only one triple repeat of Y.
(-48,-13776), (7,-13776), (41,-13776)
(There were also no duplicates.)
This implies the solution 48+7+41=96 and also
Posted by Jer
on 2016-06-22 13:37:44