I have seen in Yast->Security Centre that the value of Magic SysRq is 184. I don’t know because it has this value. By mistake (click in Configuration), I put disabled.
“184” is a magic number used only by YaST itself – the value displayed by YaST – “disabled” – is correct for the setup of SysRq in a simplistic Security setup.
I personally, only ever use the SysRq setting in the “Kernel Settings” of YaST’s “System settings”: