%I A001453 M3464 N1409
%S A001453 1,4,13,41,131,428,1429,4861,16795,58785,208011,742899,2674439,9694844,
%T A001453 35357669,129644789,477638699,1767263189,6564120419,24466267019,
%U A001453 91482563639,343059613649,1289904147323,4861946401451,18367353072151
%N A001453 Catalan numbers - 1.
%D A001453 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, 
               Academic Press, 1995 (includes this sequence).
%D A001453 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 
               (includes this sequence).
%D A001453 Baer, R. M.; Brock, P.; Natural sorting over permutation spaces. Math. 
               Comp. 22 1968 385-410.
%D A001453 J. M. Hammersley, A few seedings of research, in Proc. Sixth Berkeley 
               Sympos. Math. Stat. and Prob., ed. L. M. le Cam et al., Univ. Calif. 
               Press, 1972, Vol. I, pp. 345-394.
%F A001453 sum(binomial(n-1,j-1)*binomial(n,j-1)/j,j=2..n). - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), 
               Aug 31 2006
%p A001453 with(combstruct):bin := {B=Union(Z,Prod(B,B))}: seq (count([B,bin,unlabeled],
               size=n)-1, n=3..27); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), 
               Dec 05 2007
%p A001453 (Mupad) combinat::dyckWords::count(n)-1 $ n = 2..26; - Zerinvary Lajos 
               (zerinvarylajos(AT)yahoo.com), May 08 2008
%Y A001453 Cf. A000108, A001454. A column of A047874.
%Y A001453 Sequence in context: A070428 A052529 A049222 this_sequence A141364 A005002 
               A085507
%Y A001453 Adjacent sequences: A001450 A001451 A001452 this_sequence A001454 A001455 
               A001456
%K A001453 nonn
%O A001453 2,2
%A A001453 N. J. A. Sloane (njas(AT)research.att.com).
%E A001453 More terms from James A. Sellers (sellersj(AT)math.psu.edu), Sep 08 2000