That looks like I\!R to me, that is two separate characters, bunched together. That was the common way to produce this symbol before the AMS ... ... <看更多>
From what I can tell from https://github.com/tonsky/FiraCode/blob/master/FiraCode.glyphs, the only currently available double-struck letters ... ... <看更多>
The Double Struck font generator is a tool that converts lowercase letters to Double Struck fonts, with the new Double Struck text that can be ... ... <看更多>
Issue Summary. We are seeing inconsistent output between users for mathvariant="script", "bold-script", and "double-struck". For some (including me), ... ... <看更多>
