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%I #6 Jan 21 2014 13:07:08
%S 1,10,161,3196
%N Number of 321-avoiding extensions of comb K_{s,3}^{alpha}.
%C No formula is presently known.
%H S. Yakoubov, <a href="http://arxiv.org/abs/1310.2979">Pattern Avoidance in Extensions of Comb-Like Posets</a>, arXiv preprint arXiv:1310.2979, 2013
%K nonn,more
%O 1,2
%A _N. J. A. Sloane_, Dec 28 2013