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%I #30 Jan 02 2016 19:19:12
%S 1,1,1,1,1,0,1,0,1,1,1,0,2,0,1,0,2,0,0,0,1,0,1,0,0,0,1,0,0,0,0,0,1,1,
%T 1,0,2,0,1,0,3,0,0,0,2,0,1,0,3,0,1,0,0,0,0,0,4,0,0,0,1,0,1,0,0,0,0,0,
%U 3,0,0,0,0,0,1,0,0,0,1,0,1,0,0,0,0,0,2,0,0,0,0,0,1,0,0,0,0,0,0,0
%N Triangle read by rows: T(n,k) is the number of graphs with n vertices and k acyclic orientations.
%C Row sums give A000088.
%H FindStat - Combinatorial Statistic Finder, <a href="http://www.findstat.org/StatisticsDatabase/St000269">The number of acyclic orientations of a graph</a>.
%e Triangle begins:
%e 1,
%e 1,
%e 1,1,
%e 1,1,0,1,0,1,
%e 1,1,0,2,0,1,0,2,0,0,0,1,0,1,0,0,0,1,0,0,0,0,0,1,
%e ...
%Y Cf. A000088.
%K nonn,tabf
%O 0,13
%A _Christian Stump_, Oct 15 2015