On the number of transitive digraphs withn labeled vertices andk arcs
Tóm tắt
A computer determination of the numberT
n,k of transitive digraphs onn labeled vertices andk arcs is obtained for 2≤n≤6,0 ≤k≤n
2-n. Furthermore some formulae are given for determiningT
n,k, ∇n for extremal values ofk (namely, 0≤k≤6 andn
2
-3n+4≤k≤n
2-n).
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