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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 k chains.
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%I #8 Oct 31 2015 14:43:29

%S 1,1,1,1,1,1,2,0,1,1,1,3,3,2,2,0,3,0,0,0,1,1,1,3,5,8,5,7,4,8,2,5,1,5,

%T 0,3,0,0,0,4,0,0,0,0,0,0,0,1

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

%C Row sums give A000112.

%H FindStat - Combinatorial Statistic Finder, <a href="http://www.findstat.org/StatisticsDatabase/St000180">The number of chains of a poset</a>.

%e Triangle begins:

%e 1,

%e 1,

%e 1,1,

%e 1,1,2,0,1,

%e 1,1,3,3,2,2,0,3,0,0,0,1,

%e 1,1,3,5,8,5,7,4,8,2,5,1,5,0,3,0,0,0,4,0,0,0,0,0,0,0,1,

%e ...

%Y Cf. A000112.

%K nonn,tabf

%O 0,7

%A _Christian Stump_, Oct 28 2015