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%I #11 Jun 08 2020 05:24:10
%S 1,2,1,3,5,1,4,17,9,1,5,45,50,14,1,6,115,218,114,20,1,7,278,851,709,
%T 224,27,1,8,679,3161,3818,1867,398,35,1,9,1666,11507,19042,13113,4276,
%U 657,44,1,10,4167,41837,91383,83222,37898,8845,1025,54,1
%N Triangle read by rows: T(n,k) = number of n-element unlabeled connected N-free posets of height k (2 <= k <= n).
%H Soheir M. Khamis, <a href="https://doi.org/10.1016/S0012-365X(03)00106-7">Height counting of unlabeled interval and N-free posets</a>, Discrete Math. 275 (2004), no. 1-3, 165-175.
%e Triangle begins: 1
%e 2 1
%e 3 5 1
%e 4 17 9 1
%e 5 45 50 14 1
%e 6 115 218 114 20 1
%e 7 278 851 709 224 27 1
%e 8 679 3161 3818 1867 398 35 1
%e 9 1666 11507 19042 13113 4276 657 44 1
%e 10 4167 41837 91383 83222 37898 8845 1025 54 1
%e ...
%Y See A202178 for another version. Row sums give A202180.
%K nonn,tabl
%O 2,2
%A _N. J. A. Sloane_, Dec 13 2011
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