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%I #28 Feb 27 2020 10:31:34
%S 1,1,1,1,3,1,1,7,6,1,1,15,25,9,1,1,31,90,52,12,1,1,63,301,246,88,15,1,
%T 1,127,966,1039,510,133,18,1,1,255,3025,4083,2569,909,187,21,1,1,511,
%U 9330,15274,11790,5296,1470,250,24,1,1,1023,28501,55152,50644,27678,9706,2220,322,27,1
%N Triangle read by rows: T(n,m) (n >= 1, 1 <= m <= n) = number of set partitions of [n], avoiding 12343, with m blocks.
%H Lars Blomberg, <a href="/A250118/b250118.txt">Table of n, a(n) for n = 1..5050</a> (The first 100 rows.)
%H Harry Crane, <a href="https://ajc.maths.uq.edu.au/pdf/61/ajc_v61_p057.pdf">Left-right arrangements, set partitions, and pattern avoidance</a>, Australasian Journal of Combinatorics, 61(1) (2015), 57-72.
%e Triangle begins:
%e 1;
%e 1, 1;
%e 1, 3, 1;
%e 1, 7, 6, 1;
%e 1, 15, 25, 9, 1;
%e 1, 31, 90, 52, 12, 1;
%e 1, 63, 301, 246, 88, 15, 1;
%e 1, 127, 966, 1039, 510, 133, 18, 1;
%e 1, 255, 3025, 4083, 2569, 909, 187, 21, 1;
%e 1, 511, 9330, 15274, 11790, 5296, 1470, 250, 24, 1;
%e 1, 1023, 28501, 55152, 50644, 27678, 9706, 2220, 322, 27, 1;
%e ...
%Y Cf. A112857, A250119. For diagonals see A000392, A163941.
%K nonn,tabl
%O 1,5
%A _N. J. A. Sloane_, Nov 25 2014
%E a(46)-a(66) from _Lars Blomberg_, Aug 17 2017
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