# Sh:798

• Shelah, S., & Väänänen, J. A. The \Delta–closure of L(Q_1) is not finitely generated, assuming CH.
• Abstract:
We prove that, assuming CH, the logic \Delta(L(Q_1)) is not finitely generated. This answers a long-standing open problem
@article{Sh:798,
title = {{The $\Delta$--closure of $L(Q_1)$ is not finitely generated, assuming CH}}
}