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Triangle read by rows: T(n,k) (n>=0, k>=n+1) is the number of posets with n elements and whose chain polytope has k facets.
0

%I #11 Nov 04 2015 03:51:31

%S 1,1,1,1,1,3,1,1,7,6,2,1,13,25,18,4,2,1,22,80,111,60,32,7,4,1

%N Triangle read by rows: T(n,k) (n>=0, k>=n+1) is the number of posets with n elements and whose chain polytope has k facets.

%C Row sums give A000112.

%C Is this the same as A263858? - _R. J. Mathar_, Nov 03 2015

%H FindStat - Combinatorial Statistic Finder, <a href="http://www.findstat.org/StatisticsDatabase/St000151">The number of facets in the chain polytope of the poset</a>.

%e Triangle begins:

%e 1,

%e 1,

%e 1,1,

%e 1,3,1,

%e 1,7,6,2,

%e 1,13,25,18,4,2,

%e 1,22,80,111,60,32,7,4,1,

%e ...

%Y Cf. A000112.

%K nonn,tabf,more

%O 0,6

%A _Christian Stump_, Oct 28 2015