18.10 (2014)

A formation $\mathfrak{F}$ of finite groups satisfies the Wielandt property for residuals if whenever $U$ and $V$ are subnormal subgroups of $\langle U, V \rangle$ in a finite group $G$, then the $\mathfrak{F}$-residual $\langle U, V \rangle_{\mathfrak{F}}$ of $\langle U, V \rangle$ coincides with $\langle U_{\mathfrak{F}}, V_{\mathfrak{F}} \rangle$. Does every Fitting formation $\mathfrak{F}$ satisfy the Wielandt property for residuals?