%I #3 Mar 30 2012 16:50:20
%S 1,2,2,4,12,16,20,60,148,324,664,1600,4956,12796,27960,71596,255348,
%T 725648,1748672
%N A006967(n)/2.
%K nonn
%O 2,2
%A _N. J. A. Sloane_, Dec 02 2005
