%I
%S 1,1,0,1,0,3,0,12,2,55,22,278,182,1506,1378,8595,10040,51134,71814,
%T 314693,509200
%N The number of labeled biconnected squaregraphs with n vertices.
%D See A194088
%H Don Knuth, <a href="http://wwwcsfaculty.stanford.edu/~knuth/programs/squaregraph.w">squaregraph.w</a> (CWEB program).
%e [See A194089 for the definition of "labeling".] For n=11 the Ppentomino can be labeled in 20 ways; the 5cogwheel in only 2; hence a(11)=22.
%e The values of a(1) and a(2) depend on whether or not one believes that
%e the small complete graphs K_1 and K_2 respectively are biconnected.
%o (CWEB) (see Knuth link).
%Y Cf. A194088, A194089, A194090, A194091, A194092.
%K nonn,hard,more
%O 1,6
%A _Don Knuth_, Aug 15 2011
