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A007984 Number of essential graphs with n nodes (in 1-1 correspondence with Markov equivalence classes of acyclic digraphs). 5

%I #21 Feb 09 2024 10:28:07

%S 1,2,11,185,8782,1067825,312510571,212133402500,326266056291213,

%T 1118902054495975181,8455790399687227104576,

%U 139537050182278289405732939,4991058955493997577840793161279

%N Number of essential graphs with n nodes (in 1-1 correspondence with Markov equivalence classes of acyclic digraphs).

%D S. B. Gillispie and M. D. Perlman, Enumerating Markov equivalence classes of acyclic digraph models, Proc. of Conf. on Uncertainty in Artificial Intelligence (2001), 171-177.

%D S. B. Gillispie and M. D. Perlman, The size distribution for Markov equivalence classes of acyclic digraph models, Artificial Intelligence, 141 (2002), 137-155.

%D Bertran Steinsky, Enumeration of Labelled Essential Graphs, Ars Comb., 111, (2013), 485-494

%H S. B. Gillispie and M. D. Perlman, <a href="http://stat.washington.edu/www/research/reports/2001/tr392.pdf">Enumerating Markov equivalence classes of acyclic digraph models</a>, Univ. of Washington, Dept. of Statistics, Technical Reports.

%H S. B. Gillispie and M. D. Perlman, <a href="http://stat.washington.edu/www/research/reports/2001/tr400.pdf">The size distribution for Markov equivalence classes of acyclic digraph models</a>, Univ. of Washington, Dept. of Statistics, Technical Reports.

%Y Cf. A368569 (refined by # arcs).

%K nonn

%O 1,2

%A David Madigan (madigan(AT)stat.washington.edu)

%E More terms from Steven B. Gillispie (gillisp(AT)u.washington.edu), Oct 21 2003

%E a(10) corrected by Steven B. Gillispie (gillisp(AT)u.washington.edu), Aug 14 2007, who says: I have learned from _Bertran Steinsky_ (who determined the correct number) that there was an error in my computer software that computed a(10). The correct value is 1118902054495975181.

%E a(11)-a(13) from _Bertran Steinsky_, Jun 24 2013

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Last modified May 19 13:25 EDT 2024. Contains 372694 sequences. (Running on oeis4.)