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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A350783 Triangle read by rows: T(n,k) is the number of n-element unlabeled N-free posets with k connected components.

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%I A350783 #10 Jul 01 2022 09:39:56
%S A350783 1,1,1,3,1,1,9,4,1,1,31,12,4,1,1,115,46,13,4,1,1,474,173,49,13,4,1,1,
%T A350783 2097,727,188,50,13,4,1,1,9967,3195,795,191,50,13,4,1,1,50315,15017,
%U A350783 3502,810,192,50,13,4,1,1
%N A350783 Triangle read by rows: T(n,k) is the number of n-element unlabeled N-free posets with k connected components.
%H A350783 Salah Uddin Mohammad, Md. Shah Noor, and Md. Rashed Talukder, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL25/Uddin/uddin6.html">An Exact Enumeration of the Unlabeled Disconnected Posets</a>, J. Int. Seq., Vol. 25 (2022), Article 22.5.4.
%e A350783 Triangle begins:
%e A350783       1;
%e A350783       1,     1;
%e A350783       3,     1,    1;
%e A350783       9,     4,    1,   1;
%e A350783      31,    12,    4,   1,   1;
%e A350783     115,    46,   13,   4,   1,  1;
%e A350783     474,   173,   49,  13,   4,  1,  1;
%e A350783    2097,   727,  188,  50,  13,  4,  1, 1;
%e A350783    9967,  3195,  795, 191,  50, 13,  4, 1, 1;
%e A350783   50315, 15017, 3502, 810, 192, 50, 13, 4, 1, 1;
%e A350783   ...
%Y A350783 Row sums give A202182.
%Y A350783 Column 1 is A202180.
%Y A350783 Cf. A263864 (all posets), A349488 (disconnected).
%K A350783 nonn,tabl
%O A350783 1,4
%A A350783 _Salah Uddin Mohammad_, Jan 16 2022