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%I #8 Mar 11 2021 07:24:05
%S 9,21,166,317,596,4167,26448,48970,90652,302042
%N The number of polyominoes with n cells which support p4 tiling of the plane.
%H T. Horiyama and M. Samejima, <a href="http://cccg.ca/proceedings/2009/">Enumeration of polyominoes for p4 tiling</a>, 21st Canad. Conf. Comput. Geometry, CCCG 2009 (2009), Table 1.
%K nonn,more
%O 4,1
%A _R. J. Mathar_, Mar 11 2021