Hussar
Legend
Well, apart from Appendix N, and being "mentioned" in the AD&D DMG Credits and Acknowledgements, Jack Vance is "mentioned" by name on p.40 of the rulebook as the inspiration of the magic system and on p.112 under ongoing campaigns. Eyes of the Overlord and Planet of Adventure are "mentioned." I suppose technically you can claim AD&D is not D&D.
Yup, buried amonst what 300 ish pages of Gygaxian prose is the name of Jack Vance. In a book that's been out of print for twenty years.
Sure, among D&D players, and a very, very small subset of those who've actually READ the 1e DMG, Vance might be known. But a common name that's recognized outside of that subset? Let's be realistic here.
Why is it so hard to believe that an author that has been out of print for longer than most players have been alive is obscure.
Next you're going to tell me that Leigh Brackett is a household name as well. Can you tell me what she wrote without looking it up?