Problem:
Find the number of ordered triples of pairwise distinct integers such that and .
Solution
Solution:
Answer: 117690
We will find the number of such triples with . The answer to the original problem will then be six times what we will get. By symmetry, the number of triples with is equal to the number of those with . Our main step is thus to find the number of triples with sum .
If , then , and there are such triples. We will count the number of such triples with since the number of those with will be equal by symmetry.
For all positive such that , if , there are pairs such that and , and for all positive such that , if , there are also such pairs . In total, we have triples in the case (and hence likewise for .)
In total, there are triples such that and . Since there are triples such that , the number of triples with the additional restriction that is . So the answer to the original problem is .