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%I #15 Jan 10 2023 07:26:59
%S 0,0,1,1,6,30,232,2762,50814,1420183,58836784
%N Number of biconnected graphs on n nodes with chromatic number 3.
%H Keith M. Briggs, <a href="http://keithbriggs.info/cgt.html">Combinatorial Graph Theory</a>
%Y A diagonal of triangle in A126749.
%Y The sequence for "connected" is A126737.
%K nonn,more
%O 1,5
%A _N. J. A. Sloane_, Feb 18 2007
%E a(11) from _Michael Sollami_, Feb 18 2012