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%I #5 Mar 30 2013 04:51:09
%S 1,1,4,4,16,17,72,79
%N Sequence a_{s_n} arising in enumeration of arrays of directed blocks (see Quaintance reference for precise definition), where a_n = A129878, s_n = A129873.
%D Jocelyn Quaintance, Combinatoric Enumeration of Two-Dimensional Proper Arrays, Discrete Math., 307 (2007), 1844-1864.
%F See Quaintance reference for generating functions that produce A129872-A129886.
%K nonn,more
%O 1,3
%A _N. J. A. Sloane_, May 26 2007