I think the character Rich needs is readily available in LyX: "miscellaneous-AMS" palette, 6th row, 2nd column, "complement" character.
I can use it (in LyX 1.6.5) without any special package. Regards, Daniel Paul Elliott wrote: > On Fri, Jun 11, 2010 at 07:29:56PM -0700, Rich Shepard wrote: > > On Fri, 11 Jun 2010, Paul Elliott wrote: > > > >> In TOPOLOGY by James Dugundji a wierd script 'C' Character is used to > >> indicate the complement of a set. How do I make that character in lyx? > > > > Look in the LaTeX symbol guide. It's a pdf file that's been mentioned on > > this list several times. > > > > Rich > > I had to add /usemathpackage{mathrsfs} to the preamble and \mathsrc{C} > to the text. > -- Daniel CLEMENT