Vida Dujmović, David Eppstein, Robert Hickingbotham, Pat Morin, ·2020-11-09·via math.CO updates on arXiv.org
We describe a family of graphs with queue-number at most 4 but unbounded stack-number. This resolves open problems of Heath, Leighton and Rosenberg (1992) and Blankenship and Oporowski (1999).