Diameters of duals are linear
نویسنده
چکیده
For every oriented tree T there exists a graph DT (called the dual of T ) such that T 6→ G ⇔ G → DT holds for every G (an arrow denotes the existence of a homomorphism). An explicit construction of DT has been found recently. Although the DT constructed this way may have exponential number of vertices in |V (T )| = n, we will prove that its diameter is linear in n (and therefore DT is ”small” in some sense).
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