%I A000721 M1721 N0683
%S A000721 1,2,6,74,169112,39785643746726
%N A000721 Number of balanced Boolean functions of n variables.
%D A000721 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, 
               Academic Press, 1995 (includes this sequence).
%D A000721 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 
               (includes this sequence).
%D A000721 B. Elspas, Self-complementary symmetry types of Boolean functions, IEEE 
               Trans. Electron. Computers, 9 (1960), 264-266.
%D A000721 E. M. Palmer and R. W. Robinson, Enumeration of self-dual configurations, 
               Pacific J. Math., 110 (1984), 203-221.
%H A000721 <a href="Sindx_Bo.html#Boolean">Index entries for sequences related to 
               Boolean functions</a>
%Y A000721 Sequence in context: A061296 A019993 A065410 this_sequence A136306 A076146 
               A114552
%Y A000721 Adjacent sequences: A000718 A000719 A000720 this_sequence A000722 A000723 
               A000724
%K A000721 nonn,nice,easy,more
%O A000721 1,2
%A A000721 N. J. A. Sloane (njas(AT)research.att.com).