Y Combinator is trying an experiment this funding cycle. We’re
going to have a separate application track for groups that don’t
have an idea yet.

So if the only thing holding you back from starting a startup is
not having an idea for one, now nothing is holding you back. If
you apply for this batch and you seem like you’d make good founders,
we’ll accept you with no idea and then help you come up with one.
(We’ll consider single founders too, but we prefer groups.)

Learn how to apply to YC without an idea here