The Generalized Continuum Hypothesis is the assertion that $2^\kappa=\kappa^+$ for all infinite cardinals $\kappa$, or in other words that the power set of a set of size $\kappa$ has the next larger cardinal size above $\kappa$.
If we consider all cardinals, rather than only the infinite cardinals, then the two provable instances of this equation occur in the following vacuous and near-vacuous facts:
The power set of a set with $0$ members has $1$ member.
The power set of a set with $1$ member has $2$ members.
All other instances of $2^\kappa=\kappa^+$, finite or infinite, are either false or independent of ZFC.