Could return false positives in case of Pythagorean triplets.

risky, you may exceed int size at some point.

"already approved some time ago"

Seems approved.

Cool idea, nice catch :)

No. There was not any reason for that. Test examples added in description.

Any particular reason for removing the csharp test examples from the Description?

Added one more test and changed the datatype (int => long) in random tests because of the parameter type in the method ExpandedForm.

Is there something wrong with the current C# translation?

Go translation added. Let it go :)

Random tests added.

How about random tests?

.