%I #5 Mar 30 2012 17:28:44
%S 1,3,7,28,98,432,1846,8455,38764,181840,858387,4093460,19635210,
%T 94757550
%N Number of free polyIH15tiles (polydrops) (holes allowed) with n cells.
%D Branko Gruenbaum and G. C. Shephard, Tilings and Patterns. W. H. Freeman, New York, 1987, Sections 6.2 and 9.4.
%H Brendan Owen, <a href="http://web.archive.org/web/20061229103047/http://members.optusnet.com.au/polyforms/2dforms/polydrops/index.htm">Polydrops</a> (gives a(1)a(10))
%Y Cf. A197958.
%K hard,nonn
%O 1,2
%A _Joseph Myers_, Oct 19 2011
