Color

From https://r-graph-gallery.com/38-rcolorbrewers-palettes.html

RColorBrewer::display.brewer.all()

From https://colorspace.r-forge.r-project.org/

colorspace::hcl_palettes("sequential (multi-hue)", n = 7, plot = TRUE)

From https://github.com/thomasp85/scico

scico::scico_palette_show()

From https://sape.inf.usi.ch/quick-reference/ggplot2/colour

d=data.frame(c=colors(), y=seq(0, length(colors())-1)%%66, x=seq(0, length(colors())-1)%/%66)
ggplot2::ggplot() +
  ggplot2::scale_x_continuous(name="", breaks=NULL, expand=c(0, 0)) +
  ggplot2::scale_y_continuous(name="", breaks=NULL, expand=c(0, 0)) +
  ggplot2::scale_fill_identity() +
  ggplot2::geom_rect(data=d, mapping=ggplot2::aes(xmin=x, xmax=x+1, ymin=y, ymax=y+1), fill="white") +
  ggplot2::geom_rect(data=d, mapping=ggplot2::aes(xmin=x+0.05, xmax=x+0.95, ymin=y+0.5, ymax=y+1, fill=c)) +
  ggplot2::geom_text(data=d, mapping=ggplot2::aes(x=x+0.5, y=y+0.5, label=c), colour="black", hjust=0.5, vjust=1, size=3)