%I #3 Jan 09 2009 03:00:00
%S 1,1,3,13,33,81,189
%N Sum of coefficients of a polynomial associated to a family of digraphs.
%D Paper in preparation (1998).
%K nonn
%O 0,3
%A Ottavio D'Antona (dantona(AT)dsi.unimi.it)