This result is almost certainly bullshit, but there is nothing wrong in principle with a non constructive proof. Sometimes it is much easier to prove a counter

This result is almost certainly bullshit, but there is nothing wrong in principle with a non constructive proof. Sometimes it is much easier to prove a counterexample exists than to demonstrate that a specific number is a counterexample. Here's the canonical example of this: We want to show that there exists irrational numbers a, b s.t. a^b is rational (with b != 0). If sqrt(2) ^ sqrt(2) is rational then we are done. Otherwise, (sqrt(2) ^ sqrt(2)) ^ sqrt(2) = 2 so that is a counterexample. In this case, it is possible to prove that sqrt(2) ^ sqrt(2) is irrational, but this requires much more work.