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A267390 Number of acyclic orientations of the Turán graph T(n,10). 2

%I #7 Feb 18 2017 08:39:32

%S 1,1,2,6,24,120,720,5040,40320,362880,3628800,36288000,402796800,

%T 4906137600,64988179200,929459059200,14266826784000,233845982899200,

%U 4075249496774400,75225258805132800,1465957162768492800,28530213421847558400,586170618419794464000

%N Number of acyclic orientations of the Turán graph T(n,10).

%C An acyclic orientation is an assignment of a direction to each edge such that no cycle in the graph is consistently oriented. Stanley showed that the number of acyclic orientations of a graph G is equal to the absolute value of the chromatic polynomial X_G(q) evaluated at q=-1.

%H Alois P. Heinz, <a href="/A267390/b267390.txt">Table of n, a(n) for n = 0..450</a>

%H Richard P. Stanley, <a href="http://dx.doi.org/10.1016/0012-365X(73)90108-8">Acyclic Orientations of Graphs</a>, Discrete Mathematics, 5 (1973), pages 171-178, doi:10.1016/0012-365X(73)90108-8

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Tur%C3%A1n_graph">Turán graph</a>

%F a(n) ~ n! / (9 * (1 - log(10/9))^(9/2) * 10^n * (log(10/9))^(n+1)). - _Vaclav Kotesovec_, Feb 18 2017

%Y Column k=10 of A267383.

%K nonn

%O 0,3

%A _Alois P. Heinz_, Jan 13 2016

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Last modified April 23 20:33 EDT 2024. Contains 371916 sequences. (Running on oeis4.)