You might just email info@ycombinator.com but I am glad you asked, because the comments are very motivational. I could care less about the fact it has happened, because personally I have applied 1 time and never been interviewed, but the comments that said
yes and backed it up with stories are very inspirational.
For example, reading about a company that interviewed 4 times then was accepted, it just demonstrates the kind of persistence and courage to pursue goals (when others would likely criticize or give up) that we should all strive to emulate.
Finally, to the OP I read your profile and I wish you the greatest success, I hope you land your dream job or start the most successful YC company to date.