Okabe-Ito and grayscale color palette for Inkscape
A color palette for Inkscape with the seven Okabe-Ito colors, black, white and several grays, and a transparent (i.e. none) color.
Place this file in the path for your operating system (you probably need administrator privileges):
Linux: /usr/share/inkscape/palettes
MacOS: /Applications/Inkscape/Contents/Resources/Palettes/ (not sure if this is right)
Windows: c:/Program Files/Inkscape/Share/Inkscape/Palettes