Good observation @fluke - in finding that 2 must be involved.
Please check these two.
^ not a prime
I guess I fell in my own trap. whats the key lesson that i can make a note of?
Doubt yourself when using plugging in. It is not good to make statement sufficient.
Here, you knew even 2 must be involved, which is a good thing. You also knew Odd+Even=Odd; Just that you didn't check enough possibilities.
Ah!!! Looks good!!! Sufficient.
Not so good; Whenever you use plugin, such as in this case, try numbers beyond 10 or even 20. Something different.
23 is odd; but cant be represented as two distinct prime.
Also, we knew 2 must be involved. So, just fix it in our sets;
Guess that's about it.